Solve for x when x is between 0 and 360

tan2x+1=0

This is what i did:

tan2x+1=0

tan2x= -1

the places where tan = -1 between 0 and 360 are

135, 315, 495, and 675 (divided these by 2 to get the actual angles)

Actual angles are:

67.5,157.5,202.5,337.5

Those were my answers..

the answer in the back of the book is 0 degrees

I don't understand this??

What am i missing