Edit nevermind, I got it.
sub values in
Can someone show me how to get the final answer of cos2t for
Find the derivative of w = xy with respect to t along the path x = cost and y = sint.
I know it's chain rule for partials but i'm still confused on how to obtain that final answer.
Well, by subbing in those values, we get:
you defined earlier that and
so by subbing these to values into
we get:
using trigonometric identity
we can see that
and finally we can use trig identity:
Hope the more elaborated explanation makes more sense,