35 multiple-choice questions in College Board exam style. Each has four choices and a full explanation of why each option is right or wrong.
Anchor everything to the unit circle. Values, signs by quadrant, and identities all come from (cos θ, sin θ). Know the special angles cold.
Match each sinusoidal parameter to its effect. a is amplitude, b sets the period (2π/|b|), c is the phase shift, d is the midline.
Remember periodicity. A trig equation has infinitely many solutions: add multiples of the period, and watch the interval the question asks for.
Work in radians unless told otherwise, and read the explanations even when you got it right.