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Prove that

tan 8θ - tan 6θ - tan 2θ = (tan 8θ)(tan 6θ)(tan 2θ)

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

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Proof

*Last edited by Agnishom (2014-05-04 22:20:19)*

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,797

hi Agnishom,

Nice solution! But check line 5 out of 6.

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,640

Agnishom wrote:

Prove that

tan 8θ - tan 6θ - tan 2θ = (tan 8θ)(tan 6θ)(tan 2θ)

I haven't looked at your proof, but here's what I would do:

tan8θ - tan6θ - tan2θ

= tan8θ-(tan6θ + tan2θ)

= tan8θ - tan(6θ + 2θ)(1 - tan6θ * tan2θ)

= tan8θ - tan8θ * (1 - tan6θ * tan2θ)

= tan8θ(1 - 1 + tan6θ * tan2θ)

= tan8θ * tan6θ * tan2θ

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Fixed it, Bob

Shivam, That is the same thing I've done. Thanks for helping, though.

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

'You have made another human being happy. There is no greater accomplishment.' -bobbym

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**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 6,797

Bob

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

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