Posted by **gnozahs** on Friday, June 5, 2009 at 1:49am.

If f(x)=4sinx/1+cosx

then f'(x)=_____?

I think that the derivative of 4sinx would be 4cos and cosx would be sinx but I don't know where to go from there.

- Calculus -
**MathMate**, Friday, June 5, 2009 at 7:38am
put u=4sin(x), and v=(1+cos(x)),

then use the quotient rule:

d(u/v)= (v du/dx - u dv/dx) / v^{2}

- Calculus -
**MathMate**, Friday, June 5, 2009 at 7:41am
Sorry, I didn't see the comment the first time,

d(cos(x))/dx = -sin(x)

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