# Trigonometric related equations

I am trying to solve a few problems here. Any help on anyone of the following would be appreciated. Please show your work.

1. tan(2x) + sin(2x) / 2cos(x^2)

2. 2cos(pi / 4 + x)cos(pi /4 - x )

3. sin(3x) - 3sin(x) / cos(3x) + 3cos(x)

Whoa!

on #3, do you mean sin(3x) + 3cos(x) - (3sin(x)/cos(3x)), or (sin(3x) - 3sin(x)) / (cos(3x) + 3cos(x))

LOL

That is a classic Math related classroom quote…

Ok, Sorry to post that, but I couldn’t help it…

(Forgive Me?)

sin(3x) - 3sin(x) / cos(3x) + 3cos(x)

Let me try writing it over:

sin3x - 3sinx / cos3x + 3cosx

Hope this helps

Could you elaborate on what problems you are trying to solve …

A trigonometric equation can be expressed in a great variety of forms (infinity, if you consider each sin[f(x)+2pi*n]) unique). There are wonderful trig formulas that can change your equations to equations involving higher powers, or lower powers, sin x or sin nx, etc. and etc. to your heart’s content – and each has its purpose and use, depending on the problem at hand. But you don’t have an equation here to solve (e.g., sin2x/3cosx=5) … so are you trying to reduce, expand, evaluate, enjoy?