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# C3/4 trig proof help watch

1. Sinx / (1+sinx) = tanx(secx - tanx)

Cosec^2x(tan^2x - sin^2x) = tan^2x

Ive been trying to solve these for a while and I just can't, sorry it's not in latex I'm on my phone
2. Cosécante part = 1/sin^2x then expand
Tan^2x is sin^2x/cos^2x try using this And putting these forms in to get The answer.
3. You just need to know the reciprocal identities and difference of two squares might be helpful for the first one.

For the second one, express everything in terms of sin and cos, then go from there.
4. (Original post by Anfanny)
Cosécante part = 1/sin^2x then expand
Tan^2x is sin^2x/cos^2x try using this And putting these forms in to get The answer.
I ended up with cot^2x which is 1/tan^2x where could I have gone wrong?

Edit- nevermind I put cosecx instead of secx :/

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