## bretm Group Title need help with a integral (sin^2(t)cos^4(t)), I can split it up into: ((1-cos(2t))/2)((1+cos(2t))/2)^2, but the solution then takes out the constants and make it so its 1/8 infront of the integral, how do you get 1/8? I can get 1/4 but not 1/8 one year ago one year ago

1. TuringTest

The way I would do it is to apply$\sin^2t=1-\cos^2t$them use the double angle formula$\cos^2t=\frac12(1+\cos(2t))$

2. hartnn

you wanted to know how we get 1/8 ? [(1-...)/2 ] [(1+...)/2]^2 = [1/2-.....] [1/4+ ...] = [1/8 +....]

3. bretm

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4. bretm

ah, i see what your saying now

5. hartnn

|dw:1360780593054:dw|

6. bretm

it was taking the second part and squaring it and expanding it that was confusing but when I expanded it i forgot about what happened to my 2 on the bottom yes, thank you

7. hartnn

welcome ^_^