9. (17pts) For each of the following functions from real numbers to real numbers prove or disprove the following: The function is injective. The function is surjective. The function is bijective. If function is a bijection, then find its inverse. (a) f(x) = 2[x] +1. Note that [x] is the floor function. (b) f(x) = -10x+7 (c) f(x) = 6x +3| (d) f(x) = 5x² – 1 (e) f(x) = 2x5 – 3

Fig: 1