Hi

I am having trouble finding the x-intercepts from $\displaystyle -2\pi to 2\pi$

from the equation: $\displaystyle y=2sin(x-\frac{\pi}{4})+1$

This is what i have done but it doesn't match the book's answers:

$\displaystyle 0=2sin(x-\frac{\pi}{4})+1$

$\displaystyle \frac{-1}{2}=sin(x-\frac{\pi}{4})$

$\displaystyle x-\frac{\pi}{4}=\pi+\frac{\pi}{6},2\pi-\frac{\pi}{6},-\pi+\frac{\pi}{6},-2\pi-\frac{\pi}{6}$

$\displaystyle x=\frac{7\pi}{6}+\frac{\pi}{4},\frac{11\pi}{6}+\fr ac{\pi}{4},\frac{-5\pi}{6}+\frac{\pi}{4},\frac{-13\pi}{6}+\frac{\pi}{4}$

$\displaystyle \frac{17\pi}{12},\frac{25\pi}{12},\frac{-7\pi}{12},\frac{17\pi}{8}$

P.S