Продолжение предметного доказательства ВТФ при степени
![$n = 4$ $n = 4$](https://dxdy-02.korotkov.co.uk/f/d/8/8/d884595d37d0b1b135ceec467be5c32482.png)
Возможны два метода доказательства, кроме метода Ферма (бесконечного спуска):
- метод аналогичный методу исследования ВТФ при степени три,
- метод исследования уравненя
![$x^2 + y^4 - z^4 = 0$ $x^2 + y^4 - z^4 = 0$](https://dxdy-03.korotkov.co.uk/f/6/7/e/67e2b110cb8b3af75b63a80d2b16330882.png)
, без метода Ферма.
Для доказательства ВТФ используем уравнение
![$x^m + y^4 - z^4 = 0,\qquad\egno ( 1 ) $ $x^m + y^4 - z^4 = 0,\qquad\egno ( 1 ) $](https://dxdy-04.korotkov.co.uk/f/b/9/f/b9f28ed801e9f1e8410d5b9b33e6992682.png)
Разложение уравнения
Вводом явной чётности переменных, имеем:
![$$(2x_1 )^m + (2y_1 + 1)^4 - (2z_1 + 1)^4 = 0,\qquad\egno
( 2),$$ $$(2x_1 )^m + (2y_1 + 1)^4 - (2z_1 + 1)^4 = 0,\qquad\egno
( 2),$$](https://dxdy-04.korotkov.co.uk/f/b/c/a/bcaadd165e66a8fa39e34e2bb366910882.png)
![$$\left( {2x_1 + 1} \right)^m + \left( {2y_1 + 1} \right)^4 - \left( {2z_1 } \right)^4 = 0,\qquad\egno ( 3 ),$$ $$\left( {2x_1 + 1} \right)^m + \left( {2y_1 + 1} \right)^4 - \left( {2z_1 } \right)^4 = 0,\qquad\egno ( 3 ),$$](https://dxdy-04.korotkov.co.uk/f/f/f/6/ff606666974feda1321098cd5ac2ae3682.png)
![$$\left( {2x_1 + 1} \right)^m + \left( {2y_1 } \right)^4 - \left( {2z_1 + 1} \right)^4 = 0,$$ $$\left( {2x_1 + 1} \right)^m + \left( {2y_1 } \right)^4 - \left( {2z_1 + 1} \right)^4 = 0,$$](https://dxdy-02.korotkov.co.uk/f/1/0/6/1065f3e050315313e0b5b21e77ba9fb982.png)
Для доказательства ВТФ необхоимо исследовать первые два уравнения.
Исследование уравнения:![$\[\left( {{\text{2x}}_{\text{1}} } \right)^m = \left( {{\text{2z}}_{\text{1}} + {\text{1}}} \right)^4 - \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^4 \]$ $\[\left( {{\text{2x}}_{\text{1}} } \right)^m = \left( {{\text{2z}}_{\text{1}} + {\text{1}}} \right)^4 - \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^4 \]$](https://dxdy-04.korotkov.co.uk/f/b/8/e/b8e2efb6e57691da0b1ebb9973ec855682.png)
Исследование возможно при использовании частных свойств уравнения.
Применение методов доказательства требуют введения понятий, определяющих некоторые свойства полиномиальных диофантова уравнений:- уравнение неопределённое при значении
- уравнение определённое при значении
![$i = k,$ $i = k,$](https://dxdy-04.korotkov.co.uk/f/f/e/5/fe582235c5626078b0b8d28a026c60b482.png)
- уравнение переопределённое при значении
-
![$i - $ $i - $](https://dxdy-02.korotkov.co.uk/f/d/1/b/d1bcdc09d8147bef219bdd2562aec73982.png)
значение степени
-
![$k - $ $k - $](https://dxdy-02.korotkov.co.uk/f/1/4/d/14d8c93d8737ce738113ef204e38f59d82.png)
число неизвестных
При степени
![$n = 4$ $n = 4$](https://dxdy-02.korotkov.co.uk/f/d/8/8/d884595d37d0b1b135ceec467be5c32482.png)
уравнение переопределённое, ибо значение степени
![$f\left( {y,z} \right)$ $f\left( {y,z} \right)$](https://dxdy-02.korotkov.co.uk/f/9/d/9/9d9ecad0ff59acb8f460abb78e392a5c82.png)
больше числа неизвестных
![$f\left( {y,z} \right)$ $f\left( {y,z} \right)$](https://dxdy-02.korotkov.co.uk/f/9/d/9/9d9ecad0ff59acb8f460abb78e392a5c82.png)
. Так как число неизвестных два, уравнение определено при двух линейных сомножителях. Решение переопределённого уравнения Ферма возможно, если полученные из двух линейных сомножителей значения переменных в третьем сомножителе дают отвечающее оночлену число степени m. Из сказанного следует, что при одночлене с одним неизвестным и двух неизвестных
![$f\left( {y,z} \right)$ $f\left( {y,z} \right)$](https://dxdy-02.korotkov.co.uk/f/9/d/9/9d9ecad0ff59acb8f460abb78e392a5c82.png)
показатели степени сомножителей неоднородного уравнения порознь равны m, и можем писать:
![$$\[x_1^m = {\text{V}}_{\text{1}}^{\text{m}} {\text{V}}_{\text{2}}^{\text{m}} {\text{V}}_{\text{3}}^{\text{m}} ,{\text{(V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{,V}}_{\text{3}} ) = {\text{d}} = 1.\]$$ $$\[x_1^m = {\text{V}}_{\text{1}}^{\text{m}} {\text{V}}_{\text{2}}^{\text{m}} {\text{V}}_{\text{3}}^{\text{m}} ,{\text{(V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{,V}}_{\text{3}} ) = {\text{d}} = 1.\]$$](https://dxdy-04.korotkov.co.uk/f/f/3/6/f36860b87ce6c91a056a649ebf067f4c82.png)
Приведением к неоднородному виду, при использовании частных свойств, имеем:
![$$\[{\text{x}}_{\text{1}}^m = \frac{{\left( {2{\text{z}}_{\text{1}} + 1} \right)^4 - \left( {2{\text{y}}_{\text{1}} + 1} \right)^4 }}{{{\text{2}}^m }} = \frac{{\left( {\frac{{2{\text{z}}_{\text{1}} + 1}}
{2}} \right)^4 - \left( {\frac{{2y_{\text{1}} + 1}}{2}} \right)^4 }}
{{{\text{2}}^{m - 4} }} = \]$$ $$\[{\text{x}}_{\text{1}}^m = \frac{{\left( {2{\text{z}}_{\text{1}} + 1} \right)^4 - \left( {2{\text{y}}_{\text{1}} + 1} \right)^4 }}{{{\text{2}}^m }} = \frac{{\left( {\frac{{2{\text{z}}_{\text{1}} + 1}}
{2}} \right)^4 - \left( {\frac{{2y_{\text{1}} + 1}}{2}} \right)^4 }}
{{{\text{2}}^{m - 4} }} = \]$$](https://dxdy-03.korotkov.co.uk/f/a/6/4/a644833d0ca5daf936a9272d94b1269982.png)
![$$\[ = \frac{{\left( {{\text{z}}_{\text{1}} - {\text{y}}_{\text{1}} } \right)\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} + 1} \right)\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} + {\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} + \frac{1}{2}} \right)}}{{2^{m - 4} }} = {\text{V}}_{\text{1}}^{\text{m}} {\text{V}}_{\text{2}}^{\text{m}} {\text{V}}_{\text{3}}^{\text{m}} ,\]$$ $$\[ = \frac{{\left( {{\text{z}}_{\text{1}} - {\text{y}}_{\text{1}} } \right)\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} + 1} \right)\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} + {\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} + \frac{1}{2}} \right)}}{{2^{m - 4} }} = {\text{V}}_{\text{1}}^{\text{m}} {\text{V}}_{\text{2}}^{\text{m}} {\text{V}}_{\text{3}}^{\text{m}} ,\]$$](https://dxdy-01.korotkov.co.uk/f/0/c/8/0c8ed8d2d29e6b1ceeeb91db26d8548282.png)
![$$1.\left\{ \begin{gathered} \left( {z_1 - y_1 } \right) = 2^{m - 4} V_1^m \hfill \\ \left( {z_1 + y_1 + 1} \right) = V_2^m \hfill \\
\left( {z_1^2 + y_1^2 + z_1 + y_1 + \frac{1}
{2}} \right) = V_3^m , \hfill \\ \end{gathered} \right.$$ $$1.\left\{ \begin{gathered} \left( {z_1 - y_1 } \right) = 2^{m - 4} V_1^m \hfill \\ \left( {z_1 + y_1 + 1} \right) = V_2^m \hfill \\
\left( {z_1^2 + y_1^2 + z_1 + y_1 + \frac{1}
{2}} \right) = V_3^m , \hfill \\ \end{gathered} \right.$$](https://dxdy-01.korotkov.co.uk/f/c/6/4/c640c1330220be15be37a84b7075c84c82.png)
![$$2.\left\{ \begin{gathered} \left( {z_1 - y_1 } \right) = V_1^m \hfill \\ \left( {z_1 - y_1 } \right) = 2^{m - 4} V^m \hfill \\
\left( {z_1^2 + y_1^2 + z_1 + y_1 + \frac{1}
{2}} \right) = V_3^m , \hfill \\ \end{gathered} \right.$$ $$2.\left\{ \begin{gathered} \left( {z_1 - y_1 } \right) = V_1^m \hfill \\ \left( {z_1 - y_1 } \right) = 2^{m - 4} V^m \hfill \\
\left( {z_1^2 + y_1^2 + z_1 + y_1 + \frac{1}
{2}} \right) = V_3^m , \hfill \\ \end{gathered} \right.$$](https://dxdy-04.korotkov.co.uk/f/3/3/9/339a80b63c1e0a06e9dbbfc9decc585382.png)
На основе 1. и 2. варианта, решений нет, на основе 3. варианта, нет при степени
![${\text{m}} \geqslant {\text{4}}$ ${\text{m}} \geqslant {\text{4}}$](https://dxdy-02.korotkov.co.uk/f/d/8/e/d8e09a97afcd8d9c07b5e267edd0814382.png)
,
![$V_3^m - $ $V_3^m - $](https://dxdy-04.korotkov.co.uk/f/b/5/6/b56a963822b90e7bc93475d322bfbaf482.png)
дробь. Слеовательно, по первому методу доказательства уравнение не имеет требуемых решений. Случаи
![$1 < {\text{m}} < 4$ $1 < {\text{m}} < 4$](https://dxdy-02.korotkov.co.uk/f/9/c/5/9c5ef622af1c4e4e8f86ac0c50370db082.png)
исследуемы отдельно.
Исследование 3-го варианта решений при степени ![${\text{m}} = 2$ ${\text{m}} = 2$](https://dxdy-02.korotkov.co.uk/f/1/4/b/14bd7decdb523f400ce8ea4557b0c39082.png)
(второй метод доказательства)
Из первых двух уравнений 3-го варианта получаем значения переменных:
![$$\left\{ \begin{gathered} (z_1 - y_1 ) = V_1^2 \hfill \\
(z_1 + y_1 + 1) = V_2^2 , \hfill \\ \end{gathered} \right.$$ $$\left\{ \begin{gathered} (z_1 - y_1 ) = V_1^2 \hfill \\
(z_1 + y_1 + 1) = V_2^2 , \hfill \\ \end{gathered} \right.$$](https://dxdy-03.korotkov.co.uk/f/6/e/9/6e90a76dc6f60a5724a9f870c52f51eb82.png)
![$$\[{\text{ y}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} - {\text{1}}}}
{{\text{2}}}{\text{, y}} = {\text{2y}}_{\text{1}} + {\text{1}} = {\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} {\text{, z}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} - {\text{1}}}}
{{\text{2}}}{\text{,z}} = {\text{2z}}_{\text{1}} + {\text{1}} = {\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} {\text{. }}\]$$ $$\[{\text{ y}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} - {\text{1}}}}
{{\text{2}}}{\text{, y}} = {\text{2y}}_{\text{1}} + {\text{1}} = {\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} {\text{, z}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} - {\text{1}}}}
{{\text{2}}}{\text{,z}} = {\text{2z}}_{\text{1}} + {\text{1}} = {\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} {\text{. }}\]$$](https://dxdy-04.korotkov.co.uk/f/3/1/4/3148b857453c0992ea07ab521559beca82.png)
Подставляя значения переменных в 3. уравнение 3. варианта решений, имеем:
![$$\[{\text{V}}_{\text{3}}^{\text{2}} = \left[ {{\text{4}}\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} } \right) + 4\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} } \right) + 2} \right] = {\text{z}}^{\text{2}} + {\text{y}}^{\text{2}} = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 = 2\left( {\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} } \right),\]$$ $$\[{\text{V}}_{\text{3}}^{\text{2}} = \left[ {{\text{4}}\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} } \right) + 4\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} } \right) + 2} \right] = {\text{z}}^{\text{2}} + {\text{y}}^{\text{2}} = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 = 2\left( {\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} } \right),\]$$](https://dxdy-02.korotkov.co.uk/f/d/f/e/dfe5a867bccd36e756f68d991bc5617f82.png)
![$\[{\text{V}}_{\text{2}}^{\text{2}} > \left( {{\text{V}}_{\text{1}}^{\text{2}} + 1} \right),\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$ $\[{\text{V}}_{\text{2}}^{\text{2}} > \left( {{\text{V}}_{\text{1}}^{\text{2}} + 1} \right),\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$](https://dxdy-04.korotkov.co.uk/f/3/7/2/372d17b7cec58a1a5e5016033134fdef82.png)
числа различной чётности,
![$\[
{\text{V}}_{\text{3}}^{\text{2}} - \]$ $\[
{\text{V}}_{\text{3}}^{\text{2}} - \]$](https://dxdy-04.korotkov.co.uk/f/f/e/6/fe6be511b962395410ab4343afb36d6b82.png)
дробь.
Правая сторона уравнения чётная, значит
![$\[{\text{V}}_{\text{3}}\]$ $\[{\text{V}}_{\text{3}}\]$](https://dxdy-02.korotkov.co.uk/f/d/7/c/d7c42e46e2b0320052ac2c6b9d508e5b82.png)
тоже чётное число:
![$$\[{\text{V}}_{\text{3}}^{\text{2}} = \left( {{\text{2V}}_{\text{3}}^{\text{'}} } \right)^2 = 2\left( {{\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} } \right),{\text{ V}}_{\text{3}}^{{\text{'2}}} = \frac{{{\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} }}{2}.\]$$ $$\[{\text{V}}_{\text{3}}^{\text{2}} = \left( {{\text{2V}}_{\text{3}}^{\text{'}} } \right)^2 = 2\left( {{\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} } \right),{\text{ V}}_{\text{3}}^{{\text{'2}}} = \frac{{{\text{V}}_{\text{2}}^{\text{4}} + {\text{V}}_{\text{1}}^{\text{4}} }}{2}.\]$$](https://dxdy-02.korotkov.co.uk/f/1/7/0/1703f89de94c907896fc596aafb2f17582.png)
Чётность
![$\[\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$ $\[\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$](https://dxdy-01.korotkov.co.uk/f/4/9/1/491e8b413281f2f68de03780e4a61d0282.png)
различная, и
![$\[{\text{V}}_{\text{3}}^{\text{'}} \]$ $\[{\text{V}}_{\text{3}}^{\text{'}} \]$](https://dxdy-03.korotkov.co.uk/f/a/9/d/a9daa0321e8d4f449688b67e97e160da82.png)
не натуральное число. Это исключает разрешимость уравнения согласно требованиям при степени
![${\text{m}} = 2,{\text{n}} = 4,$ ${\text{m}} = 2,{\text{n}} = 4,$](https://dxdy-01.korotkov.co.uk/f/8/8/4/8843c22c3e35341fd9d4a90b0658611682.png)
следовательно, и при значении степени
Подстановкой в уравнение, проверим равенство:
![$$\left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^2 = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 = $$ $$\left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^2 = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 = $$](https://dxdy-04.korotkov.co.uk/f/3/3/3/333d2829f2efbc1a8ac52640d0479ea682.png)
![$$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right] = \]$$ $$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right] = \]$$](https://dxdy-04.korotkov.co.uk/f/b/7/4/b74b8b8226b3c3a56da278d68817978482.png)
![$$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right) - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right) + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right] = \]$$ $$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right) - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right) + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^2 } \right] = \]$$](https://dxdy-04.korotkov.co.uk/f/3/f/9/3f9a42bf7813dedbd87272194a76e06282.png)
Исследование 3-го варианта решений при степени ![${\text{m}} = 3$ ${\text{m}} = 3$](https://dxdy-03.korotkov.co.uk/f/6/d/d/6ddc16206925e31b247626e23364e13182.png)
(для доказательства ВТФ не требуется)
Из первых двух уравнений 3-го варианта получаем значения переменных:
![$$\left\{ \begin{gathered} (z_1 - y_1 ) = V_1^3 \hfill \\
(z_1 + y_1 + 1) = V_2^3 , \hfill \\ \end{gathered} \right.$$ $$\left\{ \begin{gathered} (z_1 - y_1 ) = V_1^3 \hfill \\
(z_1 + y_1 + 1) = V_2^3 , \hfill \\ \end{gathered} \right.$$](https://dxdy-03.korotkov.co.uk/f/2/7/4/274b7687dc59f4b05d507ccd5ef6a8fa82.png)
![$$\[{\text{z}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} - {\text{1}}}}
{{\text{2}}}{\text{ }}{\text{, z}} = {\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} {\text{, y}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} - 1}}
{2}{\text{ }}{\text{, y}} = {\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}}.\]$$ $$\[{\text{z}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} - {\text{1}}}}
{{\text{2}}}{\text{ }}{\text{, z}} = {\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} {\text{, y}}_{\text{1}} = \frac{{{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} - 1}}
{2}{\text{ }}{\text{, y}} = {\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}}.\]$$](https://dxdy-01.korotkov.co.uk/f/4/2/e/42e7c049194176577b51e94678b5c06882.png)
Поставляя значения переменных в 3. уравнение 3. варианта решений, имеем:
![$$\[{\text{2V}}_{\text{3}}^{\text{3}} = \left[ {4\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} } \right) + 4\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} } \right) + 1} \right] = {\text{z}}^{\text{2}} + {\text{y}}^{\text{2}} = \left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 = 2\left( {{\text{V}}_{\text{2}}^{\text{6}} + {\text{V}}_{\text{1}}^{\text{6}} } \right){\text{,}}\]$$ $$\[{\text{2V}}_{\text{3}}^{\text{3}} = \left[ {4\left( {{\text{z}}_{\text{1}}^{\text{2}} + {\text{y}}_{\text{1}}^{\text{2}} } \right) + 4\left( {{\text{z}}_{\text{1}} + {\text{y}}_{\text{1}} } \right) + 1} \right] = {\text{z}}^{\text{2}} + {\text{y}}^{\text{2}} = \left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 = 2\left( {{\text{V}}_{\text{2}}^{\text{6}} + {\text{V}}_{\text{1}}^{\text{6}} } \right){\text{,}}\]$$](https://dxdy-04.korotkov.co.uk/f/b/7/9/b793a08dd5f7007f51fdf90104fe152182.png)
![$\[{\text{V}}_{\text{3}}^{\text{3}} = \left( {V_2^2 } \right)^3 + \left( {V_1^2 } \right)^3 ,{\text{V}}_{\text{2}}^{\text{3}} > {\text{V}}_{\text{1}}^{\text{3}} + {\text{1}}{\text{,}}\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$ $\[{\text{V}}_{\text{3}}^{\text{3}} = \left( {V_2^2 } \right)^3 + \left( {V_1^2 } \right)^3 ,{\text{V}}_{\text{2}}^{\text{3}} > {\text{V}}_{\text{1}}^{\text{3}} + {\text{1}}{\text{,}}\left( {{\text{V}}_{\text{1}} {\text{,V}}_{\text{2}} {\text{ }}} \right) = {\text{d}} = {\text{1}} - \]$](https://dxdy-02.korotkov.co.uk/f/9/1/d/91dff3d8c6640753b6fe80fab1ad86d782.png)
различной чётности,
![$\[{\text{V}}_{\text{3}}^{\text{3}} - \]$ $\[{\text{V}}_{\text{3}}^{\text{3}} - \]$](https://dxdy-03.korotkov.co.uk/f/e/b/6/eb64e0d04b20bdb8990e05bbe624baa482.png)
дробь.
Исходя из полученного уравнения,
![$\[{\text{V}}_{\text{3}} \]$ $\[{\text{V}}_{\text{3}} \]$](https://dxdy-03.korotkov.co.uk/f/e/a/7/ea794c62a85d2696782bcf3a9741bfa882.png)
не натуральное число. Это исключает разрешимость уравнения согласно требованиям при степени
![${\text{m}} = 3,{\text{n}} = 4.$ ${\text{m}} = 3,{\text{n}} = 4.$](https://dxdy-03.korotkov.co.uk/f/a/3/4/a3440d51acef3283e9f4bfca056a14b682.png)
Подстановкой в уравнение, проверим равенство:
![$$\[\left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^3 = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 = \]$$ $$\[\left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^3 = \left( {{\text{V}}_{\text{2}}^{\text{2}} + {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 - \left( {{\text{V}}_{\text{2}}^{\text{2}} - {\text{V}}_{\text{1}}^{\text{2}} } \right)^4 = \]$$](https://dxdy-01.korotkov.co.uk/f/8/9/e/89e798102bcc8c01ed8b714970b0c92082.png)
![$$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 - \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right] = \]$$ $$\[ = \left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 - \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right] = \]$$](https://dxdy-01.korotkov.co.uk/f/4/9/5/495aee0b55034fb7fd17f696657468ba82.png)
![$$\[= \left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right) - \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right) + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right] =\]$$ $$\[= \left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right) - \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right) + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)} \right]\left[ {\left( {{\text{V}}_{\text{2}}^{\text{3}} + {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 + \left( {{\text{V}}_{\text{2}}^{\text{3}} - {\text{V}}_{\text{1}}^{\text{3}} } \right)^2 } \right] =\]$$](https://dxdy-01.korotkov.co.uk/f/4/8/6/4864077386a3612a2c4cc41f8af612b282.png)
![$$\[ = 2{\text{V}}_{\text{1}}^{\text{3}} {\text{2V}}_{\text{2}}^{\text{3}} {\text{2}}\left( {{\text{V}}_{\text{2}}^{\text{6}} + {\text{V}}_{\text{1}}^{\text{6}} } \right) = \left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^3.\]$$ $$\[ = 2{\text{V}}_{\text{1}}^{\text{3}} {\text{2V}}_{\text{2}}^{\text{3}} {\text{2}}\left( {{\text{V}}_{\text{2}}^{\text{6}} + {\text{V}}_{\text{1}}^{\text{6}} } \right) = \left( {{\text{2V}}_{\text{1}} {\text{V}}_{\text{2}} {\text{V}}_{\text{3}} } \right)^3.\]$$](https://dxdy-04.korotkov.co.uk/f/b/8/3/b83a831edd64f867bef5126d6b4aeefb82.png)
Уравнение не имеет неоднородных решений при степени
![$m \geqslant 2,n = 4,$ $m \geqslant 2,n = 4,$](https://dxdy-01.korotkov.co.uk/f/0/3/f/03f5934f29d38e5247425b520f82a0a982.png)
но имеет множество неоднородных решений при степени
![${\text{m}} = 1,{\text{n}} = 4.$ ${\text{m}} = 1,{\text{n}} = 4.$](https://dxdy-01.korotkov.co.uk/f/0/3/6/036a7dd02efb9d291cfc06abb400240e82.png)
Уравнение имеет также партикулярно однородные решений при
![$m \geqslant 2p + 1,n = 4.$ $m \geqslant 2p + 1,n = 4.$](https://dxdy-02.korotkov.co.uk/f/1/2/7/127afba52e01ea6b768ffb479c24227082.png)
При
![$\[{\text{m}} = {\text{n}}\]$ $\[{\text{m}} = {\text{n}}\]$](https://dxdy-01.korotkov.co.uk/f/c/3/7/c3750840d1da2387098e2b10559fdef882.png)
таких решений нет, ибо уравнение Ферма имело бы решение при степени
Получение партикулярно однородных решений уравнения можно, исходя из неоднородных уравнений, имеющих решение, следующим образом:
![$\[{\text{x}}^{{\text{q }}} = z^{\text{n}} - y^{\text{n}} ,{\text{x}}^{\text{q}} {\text{d}} = z^{\text{n}} d - y^{\text{n}} d,x^q = z^{\text{n}} - {\text{y}}^{\text{n}} - \]$ $\[{\text{x}}^{{\text{q }}} = z^{\text{n}} - y^{\text{n}} ,{\text{x}}^{\text{q}} {\text{d}} = z^{\text{n}} d - y^{\text{n}} d,x^q = z^{\text{n}} - {\text{y}}^{\text{n}} - \]$](https://dxdy-02.korotkov.co.uk/f/5/3/4/534ddec1a974fd8b1f36387b2b29786582.png)
уравнение, имеющее решение,
После подстановки получаем:
Для доказательства ВТФ необходимо доказать, что второе уравнение также не имеет требуемых решений.
Исследование уравнения ![$\left( {2x_1 + 1} \right)^4 + \left( {2y_1 + 1} \right)^4 - \left( {2z_1 } \right)^4 = 0$ $\left( {2x_1 + 1} \right)^4 + \left( {2y_1 + 1} \right)^4 - \left( {2z_1 } \right)^4 = 0$](https://dxdy-01.korotkov.co.uk/f/8/e/c/8ec9b41a728d977fcd58454c5853908f82.png)
Запишем уравнение при степени
![${\text{n}} = 2:$ ${\text{n}} = 2:$](https://dxdy-04.korotkov.co.uk/f/7/c/e/7ce8281c2e73ba3916b034964574e84082.png)
![$\[\left( {2z_1 } \right)^2 = \left( {{\text{2x}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} + \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^{\text{2}}.\]$ $\[\left( {2z_1 } \right)^2 = \left( {{\text{2x}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} + \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^{\text{2}}.\]$](https://dxdy-01.korotkov.co.uk/f/4/d/5/4d596e9002fcaa72564bcc0864e1b3d982.png)
Приведением уравнения к неоднородному виду, имеем:
![$$\[z_1^2 = \frac{{\left( {{\text{2x}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} + \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} }}{4} = x_1^2 + x_1 + y_1^2 + y_1 + \frac{1}
{2}.\]$$ $$\[z_1^2 = \frac{{\left( {{\text{2x}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} + \left( {{\text{2y}}_{\text{1}} + {\text{1}}} \right)^{\text{2}} }}{4} = x_1^2 + x_1 + y_1^2 + y_1 + \frac{1}
{2}.\]$$](https://dxdy-03.korotkov.co.uk/f/2/7/5/275225a63b5d2347114e23706521e34982.png)
Дробное значение
![$z_1 $ $z_1 $](https://dxdy-03.korotkov.co.uk/f/2/f/4/2f402671faef65f0531784f0a9e0db1382.png)
исключает разрешимость уравнения при значениях
![${\text{n}} = 2^{\text{k}} $ ${\text{n}} = 2^{\text{k}} $](https://dxdy-02.korotkov.co.uk/f/9/9/6/996d6d0ef6dbdc21d2eb268a4bfbfca282.png)
.
Из результатов исследования двух уравнений следует, что ВТФ при степени
не имеет требуемых решений.