An Expression in the Roots
Algebra · 26th PMO Qualifying Stage
Let $r$ and $s$ be the roots of the polynomial $x^2+2x+3$. The value of $\dfrac{1}{r^2-1}+\dfrac{1}{s^2-1}$ is
A$-\dfrac{1}{5}$
B$-\dfrac{1}{3}$
C$\dfrac{1}{5}$
D$1$