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.
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,