f(x)= sin^2x i get using the product rule, but I get stuck after 2sinx cosx

Question

f(x)= sin^2x  i get using the product rule, but I get stuck after 2sinx cosx

anonymous · Answer

what are you trying to do?

mimi_x3 · Answer

$$f(x) = (sinx)^2$$
$$f'(x) = 2(sinx)*(cosx)$$
So the trig identity is: 
$$\sin2x= 2sinxcosx$$

anonymous · Answer

also (sinx)^2 = 1/2*(1-cos2x)

mimi_x3 · Answer

Yeah, but that is hard to differentiate i guess..

anonymous · Answer

not really

anonymous · Answer

you don't have to use product rule

anonymous · Answer

just the chain for cos(2x)

mimi_x3 · Answer

I didn't use the product rule for that, i think i used the chain rule..

laddiusmaximus · Answer

I understand that. I know what the chain rule is he hasnt taught it to us yet. the example demonstrated the product rule.

anonymous · Answer

remember the formula above for when you're going to integrate sin^2(x)

mimi_x3 · Answer

@math: um, this is differentiate, i think you got kind of confused

anonymous · Answer

not really

laddiusmaximus · Answer

how would i solve this using only the product rule?

anonymous · Answer

(sinx)^2 = 1-cosx*cosx

anonymous · Answer

now you can use the product rule