We consider the following first order differential equation x' + A(t)r - B(t)r* = 0 with k an integer greater or equal to 2. a) Setting y = 2¹-k prove that

(1) is transformed into y' + (1 − k)A(t)y − (1-k)B(t) = 0 b) Use this result to solve r x = -x³. (1)