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.
To simply the expression,we should remember an ! in math represents every number (til 1) before that one multiplied or "the product of the integers from 1 to n"
So now that we have the definitions we can simplify by finding the values of each:
(9x8x7x6x5x4x3x2x1)-(4x3x2x1)(5x4x3x2x1)
After simplifying this will equal to 3600
Answer:
Please see attached picture for full solution.
The identification of parts A,B andC is illustrated below with their various reasons given.
<h3>What is an equilateral triangle?</h3>
An equilateral triangle is the triangle that has all its sides equal in length and each angle is made up of angle 60°.
Part A = The similar triangle are RGE and PBE
Part B = The triangles selected are similar because it was formed by an interception of the parallel lines of the rectangle GCPR.
Part C= All the sides of the equilateral triangle are the same therefore the distance from B to E and from P to E is the same with BP which is 225ft.
Learn more about triangles here:
brainly.com/question/2217700
#SPJ1