Please help me. anyone. i’m struggling i really would appreciate the help.

Sketch one cycle if the cosine function y=2cos2theta

Which graph represents the equation y =4x

If two angles of a triangle have equal measures and the third angle measures 90°, what are the angle measures of the triangle? a. 60°, 60°, 60° b. 45°, 90°, 90° c. 30°, 30°, 90° d. 45°, 45°, 90°