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# -RM- watch

1. -RM-
2. (Original post by UCASLord)
I'm having trouble understanding why

I am aware of the 1 = sin^2x + cos^2x identity, but I don't see how it fits into here, if indeed it does.
...

hope that helps
3. (Original post by UCASLord)
I'm having trouble understanding why cos^2^n(x) = (1 + cos^n(x))

I am aware of the 1 = sin^2x + cos^2x identity, but I don't see how it fits into here, if indeed it does.

Do you mean ??

Well that's not true as at you have LHS=1 and RHS =2
4. -RM-
5. (Original post by UCASLord)
Sorry, I meant this:

Why does cos^n(x) + cos^2n(x) = cos^n(x)(1 + cos^n(x))

6. (Original post by UCASLord)
Sorry, I meant this:

Why does cos^n(x) + cos^2n(x) = cos^n(x)(1 + cos^n(x))
Because you can factor out a from the LHS.
7. -RM-

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