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**

Let there be a triangle ABC and O a point inside it.

Now, how can I prove that:

1.

2.

*Last edited by Agnishom (2012-09-07 21:04:17)*

'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'

I'm not crazy, my mother had me tested.

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

hi Agnishom

Here's a start for number 2.

AO + OB > AB

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

I did 2.

Adding all those,

'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'

I'm not crazy, my mother had me tested.

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,972

Excellent!

I am hoping there's a similar way to do Q1 but, so far, it has eluded me.

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

I remember doing it at the 7th Grade, but what about 1.?

'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'

I'm not crazy, my mother had me tested.

Offline

**noemi****Member**- Registered: 2010-01-07
- Posts: 2,333

Hint for 1.:

OA+OB<CA+CB

*Last edited by noemi (2012-09-08 01:29:34)*

Offline

noemi wrote:

Hint for 1.:

OA+OB<CA+CB

Why?

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

I'm not crazy, my mother had me tested.

Offline

Please somebody help me!

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

I'm not crazy, my mother had me tested.

Offline

**noemi****Member**- Registered: 2010-01-07
- Posts: 2,333

OA+OB<CA+CB

OB+OC<AB+AC

OC+OA<BC+BA

adding all those you get what you need, assuming CA=AC etc.

Offline

Hmmmmmm..................

That set of problem had another problem which I shall be posting in a new thread

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

I'm not crazy, my mother had me tested.

Offline

Pages: **1**