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# Can someone explain this trig formula Watch

1. I was doing C4 solomon paper C Q6C and i have to integrate: sin^2 (2t)

And in the markscheme it says
sin^2 (2t) = 4sin^2 (t) cos^2 (t)

Can anyone explain where they got that from?
2. (Original post by Economistician)
I was doing C4 solomon paper C Q6C and i have to integrate: sin^2 (2t)

And in the markscheme it says
sin^2 (2t) = 4sin^2 (t) cos^2 (t)

Can anyone explain where they got that from?
Use the half angle formula for sin(2t).
3. (Original post by Economistician)
I was doing C4 solomon paper C Q6C and i have to integrate: sin^2 (2t)

And in the markscheme it says
sin^2 (2t) = 4sin^2 (t) cos^2 (t)

Can anyone explain where they got that from?
You should know that , so squaring both sides yields:

Edit: ninja-ed.
4. (Original post by Zacken)
You should know that , so squaring both sides yields:

Edit: ninja-ed.
You've put more effort, more likely he'll understand what you've said.
5. Is it as simple as:
Sin2x = 2SinxCosx
Sin^2 (2x) = 4Sin^2(x)Cos^2(x) ?

Edit: Oh, ok thanks for your help. I dont know why that had me stumped for so long
6. (Original post by Economistician)
Is it as simple as:
Sin2x = 2SinxCosx
Sin^2 (2x) = 4Sin^2(x)Cos^2(x) ?

Edit: Oh, ok thanks for your help. I dont know why that had me stumped for so long
Yep.

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