ответ: d²u/dxdy = cos(xy) - xy sin(xy) .
Объяснение:
u(x,y)=sin(x*y) ;
du/dx = cos(x*y) *( xy )' = y cos(x*y);
d²u/dxdy = ( y cos(x*y) )' = 1*cos(xy) - y *sin(xy) *x = cos(xy) - xy sin(xy) .
ответ: d²u/dxdy = cos(xy) - xy sin(xy) .
Объяснение:
u(x,y)=sin(x*y) ;
du/dx = cos(x*y) *( xy )' = y cos(x*y);
d²u/dxdy = ( y cos(x*y) )' = 1*cos(xy) - y *sin(xy) *x = cos(xy) - xy sin(xy) .