Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

Offline

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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,188

hi Agnishom,

Nice solution! But check line 5 out of 6.

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

Offline

**ShivamS****Member**- Registered: 2011-02-07
- Posts: 3,646

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

Offline

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'

'But our love is like the wind. I can't see it but I can feel it.' -A Walk to remember

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,188

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

Offline

Pages: **1**