Chapter 3.1, Problem 12E

Sketch the graphs of the following pdfs and find and sketch the graphs of the cdfs associated with these distributions (note carefully the relationship between the shape of the graph of the pdf and the concavity of the graph of the cdf):

(a) $f\left(x\right)=\left(\frac{2}{3}\right)x^2,-1<x<1.$.

(b) $f\left(x\right)=\frac{1}{2},-1<x<1.$

(c) $f\left(x\right)=\{\begin{array}{cc}x+1& -1<x<0\\ 1-x& 0\le x<1\end{array}$