Question

Good morning, all!

I would like assistance with finding the derivative of y = a^3 + cos^3 x.

I found the answer to be 3a^2 + cos^3 - 3 sinx ^2

I have entered it with varying parentheses into my homework URL to no avail.

I am still struggling with the chain rule, so your assistance is very much appreciated.

Thank you, fellow scholars!

Answer 1

a^3 is a constant

Answer 2

So should the answer be a^3 + (cos^3 - 3 sin x ^2)? I am still developing intuition for this material, so I need guidance on my thought process. Do you mean I should not derive 3a^2? Thank you for the clarification.

Answer 3

if a^3 is a constant its derivative is zero

Answer 4

I just resubmitted using a^3 and the answer is still incorrect.

Answer 5

o dont think that the answer is correct

Answer 6

I set the constant to zero.

Any suggestions on how to approach the problem?

My understanding is to apply the "chain rule".

The outer function for the second term "cos^3 x" is:

cos^3

The inner function for the second term is:

x

Then apply the chain rule I do the following:

d/dx f(g(x)) = f'(g(x)) * g'(x)

Answer 7

\[(a^3)'=0 therefore~ yours~is~(cos^3x)'\]