Suppose f(x,t) = e^{-6t}sin(x+2t)
(a) At any point (x,t), the differential is df=
(b) At the point (2,0), the differential is df=
(c) At the point (2,0) with dx = 0.3 and dt = -0.4, the differential is =

Question

Suppose f(x,t) = e^{-6t}sin(x+2t)
(a) At any point (x,t), the differential is df=
(b) At the point (2,0), the differential is df=
(c) At the point (2,0) with dx = 0.3 and dt = -0.4, the differential is =

zepdrix · Answer

Hmm I've only ever worked with finding derivatives of functions of multiple variables.
I don't remember finding the differential...
I would assume it holds the same form though,$$\Large\bf\sf df\quad=\quad f_x dx+f_t dt$$Mmmm yes? Maybe?

majikdusty · Answer

Oh, you are absolutely right! Thank you very much! I can finish the problem my self from here!