## Saturday, 10 September 2011

### Simple Trigonometry Formula (Hexagon Alternative Formulas)

Bismillahirrahmanirrahim...

In this entry, I'm going to share about the trigonometric formula. During my secondary school, it is very hard to remember so many formula for trigonometric functions. Especially when it comes to proving the equality of an equation. So, my friend teach me about this formula. It is very easy to use. You can derive so many formula from what I will show you below in this entry. I named this method "Hexagon Alternative Formulas".

Before I start with the Hexagon Alternative Formulas, I want to recall about the most important thing in trigonometry. It is...

It is the "Soh Cah Toa Formula"

So let's move to the "Hexagon Alternative Formulas"

There are THREE way that we can interpret the hexagon.

1. Around the Hexagon (Quotient Identities)

Just remember the position of each trigonometry elements and you can derive formulas from this hexagon. the formulas that can be derived are as below...
For example: From the first hexagon, you want to search for cot Ɵ. First you must look for the next two elements after the element cot (by following the arrow) which is cosec and then sec. So the equation is the third equation on the left above. The first element after the searched element will be the nominator and the second will be the denominator.

2. Straight Line Formulas (Reciprocal Identities)
Just see the colour of the arrow and see the formulas.
Example: From the first hexagon, if you want to search the value of tan Ɵ, you must look at the red arrow. So, the formula is the third formula.

3. Triangle Formulas (Pythagorean Identities)
So just look at the coloured arrows and you can derive the equations by yourselves.

This Hexagon Alternative Formula helped me a lot in my SPM and even in my Calculus in Foundation in Science. I'm sharing this because this trigonometry things is very nonsense thing. In order to pass the test, just memorize it. Share this with your friends...

Alhamdulillah...