Cos2x= A. cos^2x-1

B. 1-2cos^2x

C. cos^2sin^2x

D.1-2sin^2x

Please help.

Both the red and blue line segments stretch from the center of the circle to a point on the circle. the length of the blue segment is 5. how long is the red line segment?

Which equation represents the function on the graph?

Koji is installing a rectangular window in an office building. the window is 823 feet wide and 534 feet high. the formula for the area of a rectangle is a=bh. what is the area of the window? enter your answer as a mixed number in simplest form in the box. $$ ft2