Two students wrote antiderivative formulas for k sin (kx), where k > 1. Student 1: (k sin (kx))dx = k2 cos (kx) + C Student 2: (k sin (kx))dx = - cos (kx) + C Which student, if any, wrote a correct antiderivative formula? O Student 1 only O Student 2 only O both Student 1 and Student 2 O neither Student 1 nor Student 2