Solve for $x$ in each equation. Assume $x$ is measured in radians. Hint: First use a substitution to make the problem easier.

1. $2\sin^2\left(x+1\right)-\sin\left(x+1\right)-1=0$

   Step 1(a):

   Let $U=\sin\left(x+1\right)$
   so $2U^2−U−1=0$

   Step 2(a):

   Solve for $U$, then substitute to solve for $x$.

   Hint (a):

   Remember to mention ALL solutions.

2. $( x ^ { 2 } - 2 x + 1 ) - 3 \sqrt { x ^ { 2 } - 2 x + 1 } = - 2$

   Hint (b):

   Let $U = x^{2} − 2x + 1$