And in the other 4 pages we have to show various Applications of the Formula

Well, you can work out the area of a triangle when you know its sides.

I will see if I can find anything else.

Proof without trig? That may be a tough request to fulfil.

The first post on that site using the trig formulas.

The second takes a huge leap un-proved. I have a suspicion that trig will be involved there too.

I've know of a book with a proof but it'll be 24 hours before I can look it up. (and I seem to remember it has trig too)

Bob

]]>I required a proof without trigonometry

Anyway, this did help:

http://answers.yahoo.com/question/index … 924AAYZnIO

Which of this don't you understand:

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If it gives zero then it indicates that you have a "pretty doggone flat triangle." Eg. 4,5,9.

It gives a negative number under the radical when it can't be a triangle. Eg. 4,5,10. ]]>

Please give two other applications( May be two interesting problems)

Please explain the proof

I don't understand what's written on Wikpedia

You could put an example on one page. An application on a quadrilateral on another.

Oh, and, I recommend reading the Wikipeadia article on it.

]]>It has to contain a minimum of 5 pages apart from the introduction

I replace 1 of them with the proof.

And in the other 4 pages we have to show various Applications of the Formula

P.S.: Please give a proof without any Trigonometry and pls don't recommend that which is given in Wikipedia because I didn't understand it

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