# Math Help - Finding a derivative

1. ## Finding a derivative

Hello, I am hoping I could get some help with this problem:

If f(x) = 7sin(3 x) * (arcsin(x)), find f'( x ).

I'm assuming I need to use the product rule, but I am failing to set it up right. I assume it's with the beginning part and I'm just goofing up on what to do with the coefficient.

I think it's ((7sin3x)' * arcsinx) + (7sin(3x) ( 1/(sqrt(1-x^2)))

I thought the first deriv would be something like 7cos3x(3), but that doesnt seem to be right and I've tried a few other things, but cant seem to get the right answer, any help would be much appreciated.

If that's correct I'm just failing to get the derivative. I can't seem to remember how I should proceed with something in that form. I should be past this but I'm having trouble seeing it. Any help would be great.

Thank you

2. See this, click Show Steps. If you still don't understand something ask!