# Thread: Solve trig equation on interval

1. ## Solve trig equation on interval

sec^2(x) +1 = 7-tan(x)
need this badly for tomorrow!! Very confused because however I solve it (I've tried turning it into sin/cosine or tans and then factoring) it doesn't give an answer on the necessary interval, 0<x<2pi!

2. ## Re: Solve trig equation on interval

substitute $1+\tan^2{x}$ for $\sec^2{x}$ and solve the resulting quadratic in $\tan{x}$ ...