trigonometric problem

[rizaado]

Hello. I need to solve this:
(cotg18*cotg12)/(sqrt(3))-(cotg18+cotg12)
Thank you in advance.

[Moschops]

http://www.wolframalpha.com/input/?i=%28cotg18*cotg12%29%2F%28sqrt%283%29%29-%28cotg18%2Bcotg12%29

[rizaado]

Hello. I need to solve this with trigonometric functions not result in approximation!

[Chervil]

But it already uses trigonometric functions.
If you do it in C++ the result will be an approximation.

But if you did want to write it in C++, remember cot = 1/tan and angles are in radians rather than degrees.

[rizaado]

Its not a C++ problem, its math problem. And I mean formulas. But thanks. I need the steps. The answer is:
sqrt(3)/3
I have the answer but I dont have the steps. I have been trying to solve this for four hours without luck.

[Chervil]

It's a long time since I solved any problem like this. But a couple of thoughts, anything involving trig functions and sqrt(3) makes me think in terms of angles like 60 degrees and 30 degrees.
example sin(60) = cos(30) = sqrt(3)/2

Now an interesting thing about the question is the angles 12 and 18. 12+18 = 30.
There are a lot of relationships between different trigonometric functions, expressing one in terms of the other and so on. I suggest you look up some of the formulae for those relationships (sorry, I don't remember them now).

http://www.sosmath.com/trig/Trig5/trig5/trig5.html

[rizaado]

Thank you. I will try again tomorrow.

[rizaado]

Can anyone help me?

[rizaado]

I have solved the problem after eight hours.

[Ganado]

What does the g stand for in cotg?

[helios]

Maybe "cotangent of angle in gradians"?

As an aside, am I the only one who thinks the reciprocal trigonometric functions are just garbage?

[ne555]

All you need is sin

[Chervil]

Wasn't that a Beatles number?