10) If ( \log y=\tan x \), show that \( -;)\left(1+x^{2} ight) y_{2}+(2 x-1) y_{1}=0 \) \[ \ { ii) }\left(1+x^{2} ight) y_{n+2}+y_{n+1}(2 n x+2 x-1)+(n+1) y_{n} =0