Use a half-angle identity to find the exact solution of cos3pi/8

You are constructing a histogram for scores that range from 70 to 100 in whole points. frequencies range from 3 to 10; that is, every whole-point score between 60 and 100 occurs at least 3 times, and at least one score occurs 10 times. which of these would probably be the best range and size for the score intervals along the x-axis?

Determine whether the angles in each given pair are coterminal. 744°, -336°

The vertex of this parabola is at (-2, 5). which of the following could be it’s equation? a. y=3(x+2)^2-5 b. y=3(x-2)^2-5 c. y=3(x+2)^2+5 d. y=3(x-2)^2+5