No.
Use the product rule
d/dx(u*v) = u dv/dx + v du/dx
and let 5x^4 +2 = u(x), and
3 sin x = v(x)
du/dx = 20 x^3
dv/dx = 3 cos x
Derivative = 3 cos x *(5x^4 + 2)
+ 3 sin x *(20 x^3)
Find the derivative for k(x) = (5x4 + 2)(3sin x).
Would this be the answer:
(60sinx)x^3+ (15cosx)x^5+ 2
3 answers
That is how I got my answer, by using product rule.
Obviously you made a mislake somewhere along the line. If you care to show your steps, someone will show you where the error was made.