https://s0.wp.com/latex.php?latex=%5Cmid%7Bs_1%7D+%5Cmid+%3D+%5Cmid%7Bs_2%7D+%5Cmid+%3D+%5Csqrt+%7B%7B%28%5Czeta+%5Comega_n%29%5E2%7D+%2B+%28%5Comega_n+%5Csqrt%7B1-%5Czeta%5E2%7D%29%5E2%7D+%3D+%5Cpm%5Comega_n+&bg=fff&fg=444444&s=0