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# Trig identity proof watch

1. Prove that cosecx/cotx + tanx = cosx

I did 1/sinx (cosx/sinx + sinx/cosx) = cosx/sin^2x + 1/cosx

2. (Original post by G.Y)
Prove that cosecx/cotx + tanx = cosx

I did 1/sinx (cosx/sinx + sinx/cosx) = cosx/sin^2x + 1/cosx

OK, took me a while to notice that you didnt format your original equation correctly and actually meant the second one.

Anyway, so you made an error there.
3. (Original post by RDKGames)
OK, took me a while to notice that you didnt format your original equation correctly and actually meant the second one.

Anyway, so you made an error there.
I don't understand
4. sin = s
cos = c
cot = cos/sin
tan = sin/cos

(1/s) / [(c/s) + (s/c)] = LHS

=(1/s) / (c^2/sc + s^2 / sc)
=(1/s) / [(c^2 + s^2) / sc]
**c^2 + s^2 = 1**
**diving by a fraction is the same as multiplying by the reciprocal**
=1/s * (sc / 1)
=sc / s
=c
= RHS

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