Oval (S) and A, B permanent, straight line d

If you answer right ill give brainliest, : )

What is the expression equivalent to (3x^2-7)

The motion of a weight that hangs from a spring is represented by the equation h=8sin(2pi/3t). it models the weight’s height above or below the rest position as a function of time. approximately when will the object be 3 inches above the rest position?