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Another student (not you) is using the method of undetermined coefficients to solve a second-order, constant-coefficient DE, and claims to have found the homogeneous solution yn. You don't know what the differential equation is, but by looking only at the student's yn, you see that there must be a mistake. Which of the following could be the (incorrect) yh that the student found? [Hint: Which one of the following expressions is not a valid choice for yh for any second-order, constant-coefficient DE?] Select one: O A. Uh = cle2x + coxe2x O B. Uh = cle-2* + cze2x O C. Uh = cle 2x cos(4ac) + cze-27 sin(4ac) O D. Uh = C1+ C2x O E. Uh - C1 cos(x ) + c, sin(2x)Another student (not you) is using the method of undetermined coefficients to solve a second- order, constant-coefficient, non-homogeneous DE, and has found the correct homogeneous solution Uh = C1 + Cze 2. The student claims to have found a particular solution yp. You don't know what the differential equation is, but by looking only at Uh and the student's particular solution Up, you see that there must be a mistake in finding Up. Which of the following could be the (incorrect) Up that the student found? [Hint: Which one of the following expressions is not a possible choice for Up in the situation described?] Select one: O A. Up = -e-2x O B. Up = 202 - 2 + 2 O C. Up = 4xe -2x O D. Up = cos(2x ) - 2 sin(2x) O E. Up = e-5x