Evaluating the area between the curves $r=2\sin\theta$ and $r=\sin\theta+\cos\theta$ 
So the problem asked me to find the area of the region that lies inside both of the circles
$$r=2\sin\theta, \quad  r=\sin\theta +\cos\theta $$

I know that $r=2\sin\theta$ is $x^2+(y-1)^2=1,$but the second one is a little bit harder to me.
$$\begin{align*}
x&=r\cos\theta=\cos\theta(\sin\theta + \cos\theta)\\
y&=\sin\theta(\sin\theta+\cos\theta)
\end{align*}$$
so $x+y=1+2\cos\theta \sin\theta$....Which gives me no help.
I'm getting used to polar coordinates, but I need some help! Thank you

Hint: Try multiplying both sides of $r=\sin\theta + \cos\theta$ by $r$, and using the identities $r^2=x^2+y^2$, $x=r\cos\theta$, and $y=r\sin\theta$, to find an equation in terms of $x$ and $y$. 
