Question

Which of the following is a solution to tan2 x − 1 = 0?

Answer 1

tan2(x)−1=0
tan2(x)=1
tan(x)=±1√
tan(x)=1√ or tan(x)=−1√
tan(x)=1 or tan(x)=−1
x=arctan(1) or x=arctan(−1)
x=π4+πn or x=3π4+πn,x=−π4+πn or x=−3π4+πn
These solutions can be combined into the following
x=πn2−π4