Solution
= Solution
The <double-angle formula> for the <tangent function> gives $1=2t/(1-t^2)$. Here $0<t<1$, because $0<\pi/8<\pi/4$, so the denominator is nonzero. Rearranging yields the <quadratic equation>
$$
\boxed{t^2+2t-1=0.}
$$
= Solution
The <double-angle formula> for the <tangent function> gives $1=2t/(1-t^2)$. Here $0<t<1$, because $0<\pi/8<\pi/4$, so the denominator is nonzero. Rearranging yields the <quadratic equation>
$$
\boxed{t^2+2t-1=0.}
$$