2022 NJC J2 CT P1 Q3
Home 2022 NJC J2 CT P1 Q3 It is given that ${{tan }^{-1}}y=a{{tan }^{-1}}x+b$, for constants $a$ and $b$. (i) Show that $left( 1+{{x}^{2}} right)frac{{{text{d}}^{2}}y}{text{d}{{x}^{2}}}=2left( ay-x right)frac{text{d}y}{text{d}x}$. [2] (ii) Suppose