Question

prove that (sinx/(1-cotx)) - (cosx/(tanx-1)) = sinx + cosx

Answer 1

hmm what would be the basic trig identity of cotangent?

Answer 2

on LHS

take first term- chnge it to sin and cos

\[\sin x/1-(\frac{ cosx }{ sinx })= \frac{ \sin^2x }{ sinx-cosx }\]

now do the same with the 2nd term
\[ -\frac{ \cos^2x }{ sinx-cosx }\]

can you see it from here??

Answer 3

No, I can't

Answer 4

hmm what would be the basic trig identities for cot and tan functions?

Answer 5

ok put terms together

\[(\sin^2x-\cos^2x)/sinx-cosx\]

see where to go now??

Answer 6

yes, Thank you!

Answer 7

good job!!