The given equation is
[tex]\tan ^2x-1=0[/tex]
Adding 1 on both sides, we get
[tex]\tan ^2x-1+1=0+1[/tex]
[tex]\tan ^2x=1[/tex]
[tex]\tan ^2x=1^2[/tex]
Taking square root on both sides, we get
[tex]\tan ^{}x=1[/tex][tex]\text{ Use }\tan (\frac{\pi}{4})=1.[/tex]
[tex]\tan ^{}x=\tan (\frac{\pi}{4})[/tex][tex]x=\frac{\pi}{4}[/tex]
Hence the solution is
[tex]x=\frac{\pi}{4}[/tex]
Option B is correct.
