i need to find the solution for the following:

22: cos2 (x(sec2 (x) -1))

23: sec4 (x) - tan4 (x)

24: cot (x sec(x))

25:(sec2 (x) -1)/sin2 (x)

26:cos2 ((pi/20) - x)/cos(x)

I am completely lost please show me how to solve these kinds of problems.

Guest May 6, 2017

#1**+1 **

Hi,

Firstly you cannot get a solution becasue there is no equal sign.

All you can do it try to simplify them :)

I am confused about what the actual questions are.

I assume there are a number of powers here.

23: sec4 (x) - tan4 (x)

I assume

\(sec^4 (x) - tan^4 (x)\\ \qquad \text{Difference of 2 squares}\\ =(sec^2 (x) + tan^2 (x))(sec^2 (x) - tan^2 (x))\\ \qquad sec^2x=\frac{1}{cos^2x}=\frac{sin^2x+cos^2x}{cos^2} =tan^2x+1 \\ =(1+tan^2(x) + tan^2 (x))(1+tan^2x- tan^2 (x))\\ =1+2tan^2(x) \\ \)

Melody
May 6, 2017