Question

let f(x,y) = cosh(e^x + 3y) with x=e^t and y = 3t. Use total derivative rule to compute df/dt for t=0

Answer 1

df/dt=partial derivative of f w.r.t x*dx/dt+ partial der of f w.r.t y*dy/dt

Answer 2

sorry, but what is " f w.r.t x"?
what would f(x) of cosh(e^x + 3y) be? Is it sinh(e^x) ?
thank you.

Answer 3

with respect to

Answer 4

sinh(e^x+3y) e^x

Answer 5

\[df/dt=\sinh(e^x+3y) *e^x* e^t+\sin(e^x+3y)*3*3\]

Answer 6

ah! thanks! i get it now.