Prove that:
1 + 2cos(2A) + cos(4A) = 4cos(A)cos(2A)

20 points! asap! a is known to be 6,500 feet above sea level; ab = 600 feet. the angle at a looking up at p is 20°. the angle at b looking up at p is 35°. how far above sea level is the peak p? find the height of the mountain peak to the nearest foot. height above sea level =

Given: △abc, ab=15, bd=9 ad ⊥ bc , m∠c=30°. find: the perimeter of the triangle.

Rob spent 25%, percent more time on his research project than he had planned. he spent an extra h hours on the project. which of the following expressions could represent the number of hours rob actually spent on the project? two answers