Question

求z=sin(xy)+cos（的平方）(xy) 函数的偏导数~~~求具体步骤

Answer 1

令 u = x y,əu/əx = y,əu/əy = x

z = sinu + cos²u

əz/əx = [cosu - sin(2u)] * əu/əx = y [cos(x y) - sin(2x y)]

əz/əy = [cosu - sin(2u)] * əu/əy = x [cos(x y) - sin(2x y)]