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#1 2018-11-23 03:36:16
- tony123
- Member
- Registered: 2007-08-03
- Posts: 229
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
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- Registered: 2010-06-20
- Posts: 10,621
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 
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