Задача 54863 ...

5f3ea7e3faf909182968ddd9

22.10.2020 22:52:44

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[m]grad f(x;y)=f`_{x}(x;y)\cdot \vec{i}+f`_{y}(x;y)\cdot \vec{j}[/m]

1)
[m]f`_{x}(x;y)=2x+y[/m]
[m]f`_{y}(x;y)=2y+x[/m]

[m]f`_{x}(1;2)=2\cdot 1+2=4[/m]
[m]f`_{y}(1;2)=2\cdot 2+1=5[/m]

[m]grad f(x;y)_{(1;2)}=f`_{x}(1;2)\cdot \vec{i}+f`_{y}(1;2)\cdot \vec{j}=4\cdot\vec{i}+5\cdot \vec{j}[/m]

Остальные аналогично