Answer
See graph.
a. $y=2sin(x)+1$
b. see explanations.
Work Step by Step
Graph the equation as shown in the figure.
a. The graph appears to be the same as $y=2sin(x)+1$
b. Using the identity $cos(2x)=1-2sin^2x$, we have
$y=\frac{1-2(1-2sin^2x)}{2sin(x)-1}=\frac{4sin^2x-1)}{2sin(x)-1}=\frac{(2sin(x)+1)(2sin(x)-1)}{2sin(x)-1}=2sin(x)+1$
provided that
$2sin(x)-1\ne 0$