Question

prove .

Answer 1

change tan into sin/cos everywhere

Answer 2

and cot too ?

Answer 3

then u,ll have cos3A.CosA/sin2A + sin3A.SinA/Sin2A

Answer 4

dont do ath to RHS

Answer 5

okay !

Answer 6

after simplifying last expression u.ll get cos2A/Sin2A...which is RHS

Answer 7

i didn't understand the last step !

Answer 8

u got this expression....cos3A.CosA/sin2A + sin3A.SinA/Sin2A???

Answer 9

yes

Answer 10

ok then after taking LCM in numerator u have...cos3A.CosA+sin3A.SinA...which is equal to Cos(3A-A) i.e. cos2A

Answer 11

use d identity Cos(A-B)= cosAcosB+ SinA.SinB

Answer 12

okay , got it now .. thank you @akash123 :)