$$\begin{aligned} & y=\log _e\left(\frac{1-x^2}{1+x^2}\right) \\ & \frac{d y}{d x}=y^{\prime}=\frac{-4 x}{1-x^4} \end{aligned}$$

Again,

$$\frac{d^2 y}{d x^2}=y^{\prime \prime}=\frac{-4\left(1+3 x^4\right)}{\left(1-x^4\right)^2}$$

Again

$$y^{\prime}-y^{\prime \prime}=\frac{-4 x}{1-x^4}+\frac{4\left(1+3 x^4\right)}{\left(1-x^4\right)^2}$$

at $$\mathrm{x}=\frac{1}{2}$$,

$$y^{\prime}-y^{\prime \prime}=\frac{736}{225}$$

Thus $$225\left(y^{\prime}-y^{\prime \prime}\right)=225 \times \frac{736}{225}=736$$