7. For the RV X of Example 7 find the PDF of the following RVs:

(a) Y1 =eX,

(b) Y2 =

2X2 +1, and

(c) Y3 = g(X), where g(x) = 1 if x > 0, = 1/2 if x = 0, and = −1 if x < 0.