z=e^(xy)sin(x+y),则az/ax=请一步步说清楚az=?ax=?然后为什么az/ay=xe^(xy)sin(x+y)+e^(xy)cos(x+y),上下相除会变成加号

Question

z=e^(xy)sin(x+y),则az/ax=
请一步步说清楚
az=?
ax=?
然后为什么az/ay=xe^(xy)sin(x+y)+e^(xy)cos(x+y),上下相除会变成加号

Answer 1

z=e^(xy)sin(x+y)
az/ax= sin(x+y)a/ax {e^xy) + e^xy a/ax { sin(x+y) }
= y.e^(xy) sin(x+y) + cos(x+y) e^(xy)