Question

find all the points on the surface at which the tangent plane to z=x^3y^2 is horizontal. (tangent planes and normal vectors)

Answer 1

Differentiate.

Answer 2

u mean in terms of x y and z?

Answer 3

after i got the partial derivatives? what do i do?

Answer 4

you need to set that derivative = 0

Answer 5

a horizontal tangent implies a slope of zero

Answer 6

so you're looking to set the slope, or z'(x,y) = 0