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#1 2018-11-23 03:36:16

tony123
Member
Registered: 2007-08-03
Posts: 197

triangle

In triangle ABC where AB=4,BC=5,AC=6 Prove that cos 2C=cos B

Last edited by tony123 (2018-11-23 03:37:28)

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#2 2018-11-23 22:12:23

bob bundy
Administrator
Registered: 2010-06-20
Posts: 8,507

Re: triangle

Hi Tony123

I used the cosine rule thus:

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob Bundy smile

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