Answer:
4/2+ 8/2+20/5+20/5+48/5+42/4
12/2+88/5+42/4
(120+ 352+210)/20= 682/20= 341 x 1/10=34.1
The answer is x=34 degrees.
Cos(2x) = cos^2(x) - sin^2(x) - cos(x)
but sin^2(x) = 1 - cos^2(x)
cos(2x) - cos(x) = cos^2(x) - (1 - cos^2(x) ) - cos(x)
cos(2x) - cos(x) = cos^2(x) - 1 + cos^2(x) - cos(x)
cos(2x) - cos(x) = 2cos^2(x) - 1 - cos(x)
cos(2x) - cos(x) = (2cos(x) + 1)(cos(x) - 1)
I think this is what you have asked for.
Answer:
1. Multiply the value of the first variable by one of the original equations to solve for the second variable.
2. Solve for one of the variables.
3. Substitute the value of the known variable into one of the original equations to solve for the unknown variable.
Step-by-step explanation: