Find s'(t).

Does the constant multiple rule apply here?

s(t) = [-2(2-t) * sqrt{1+t}]/3

I pulled out 1/3 but my answer is nothing like the book's answer.

Applying the constant rule, the problem now looks like this:

s(t) = (1/3) times [-2(2-t) * sqrt{1+t}]

The fraction (1/3) comes along for the ride.

I then know to apply the product rule to everything else.

The answer is (t)/sqrt{1+t}. Can someone work out this problem for me? I would love to see the steps. I never post a question in this forum without working out the problem many times on my own. Please, help. Thank you.