# How to prove the following equation:cos*2(180+x)+tan(x-180)sin(720-x)cosx=cos2x

I have tried solving it but I just can't get it right

How to prove the following equation:cos*2(180+x)+tan(x-180)sin(720-x)cosx=cos2x

I have tried solving it but I just can't get it right

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Asked: ** 2017-04-13 15:12:09 +0200 **

Seen: **525 times**

Last updated: **Apr 13 '17**

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What does

`cos*2(180+x)`

mean ?Let me guess:

`bool(equ)`

yields`True`

Well...

This is the half of the cake.