Question

prove (tanx+sinx)/2tanx = cos^2(x/2)

Answer 1

try converting RHS to sin and cos

Answer 2

I did, I'm still missing something.

Answer 3

i reduced it to

(1 + cos x)
---------
2

Answer 4

i'll have to check std trig identities

sorry i meant LHS in first post

Answer 5

i think that = RHS

Answer 6

I have that also
I have tried both sides, im missing a vital identity transformation

Answer 7

So you were able to reduce LHS to (1+cos x)/2?

Answer 8

right

cos^2 x = 1 + cos2x
---------
2

Answer 9

so

cos^2 (x/2) = 1 + cos x
--------
2

Answer 10

its one of the half angle formulae

Answer 11

LOL that was the easy part, Im trying to get (tanx+sinx)/2tanx to = that.

Answer 12

ok

sin x + sin x
----
cos x
--------------
2 sin x
-----
cos x


= sinx + sinx cos x cosx
--------------- * -----
cosx 2 sinx


= sinx ( 1 + cos x)

--------------
2 sin x

= ( 1 + cosx)
----------
2

Answer 13

Thank you very much, I did not factor correctly and ended up chasing my tail.

Answer 14

yw