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some trig identity problems

I dealt with the top and bottom separately but it just seems to get even more complicated
I rewrote cot^2x with cosec^2x - 1trig id.png
(edited 8 months ago)
Reply 1
Original post by Bookworm524
I dealt with the top and bottom separately but it just seems to get even more complicated
I rewrote cot^2x with cosec^2x - 1trig id.png


you could rewrite your "-1" as the (negative) pythagorean identity which should pretty much get you there.
Reply 2
Rewrite the top as cosec^2(x) - 1 + 1 - cos^2(x), use the difference of two square, cancel out top and bottom, leave you with cosec(x) - cos(x). Which is 1/sin(x) - cos(x). Hope that help.
Reply 3
Original post by Seb S
Rewrite the top as cosec^2(x) - 1 + 1 - cos^2(x), u

Please don't post full solutions - it is against the rules of the forum! Stick to a hint and then the OP can have a go for themselves :smile:

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