Yahoo! Quesiton Answer

Hi!
      Here's the solution:

f'(x) = -sin(sqrt(5x + 2)) * (d(sqrt(5x + 2)) / dx) (Chain Rule)
 = -sin(sqrt(5x + 2)) * (1/[2*sqrt(5x + 2)]) * d(5x + 2) / dx
=  -sin(sqrt(5x + 2)) * (1/[2*sqrt(5x + 2)]) *  5


Hope it helps.

Good luck!
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