Question

In xyz-space, an equation of the plane tangent to the surface z=sin(y)e^(-x) at the point where x=0 and y=(π/2) is

(A) x+y=1
(B) x+z=1
(C) x−z=1
(D) y+z=1
(E) y−z=1

Answer 1

did you find the gradient?

Answer 2

the gradient is normal to the surface, and so, normal to the tangent plane...

Answer 3

you there?

Answer 4

I'll try the gradient and see what I get.

Answer 5

\[<-\sin y*e^{-x} i + \cos y *e^{-x} j - k>\]

Answer 6

for x=1, y=pi/2
it is <-i -k>