SamverkanFlervariabelanalysLIU

a) \displaystyle \nabla f=(yz,\ xz,\ xy)

b) \displaystyle \nabla f=(\arctan (y/z),\ \frac{xz}{z^2+y^2},\ \frac{-xy}{z^2+y^2})

c) \displaystyle \nabla f=(yz x^{yz-2},\ z\ln x \, (x^y)^z,\ y\ln x \, (x^y)^z)