If $\dfrac{x^2}{f(4a)}=\dfrac{y^2}{f(a^2-5)}$ respresents and ellipse with major axis as y-axis and $f$ is a decreasing function, then

দৃশ্যকল্প-I: $y(x+1)(x+2)-x+4$

দৃশ্যকল্প-II: $\mathrm{g}(\mathrm{x})=3 \mathrm{x}^{3}-6 \mathrm{x}^{2}-5 \mathrm{x}+1$

If for all $x, y$ the function f is defined by; $f(x)+f(y)+f(x)\cdot f(y)=1$ and $f(x) > 0$.When $f(x)$ is differentiable $f'(x)=$,

(0, 9) ব্যবধিতে f(x)=x³-18x²+96x ফাংশনের  সর্বোচ্চ মান কত ?  

The critical points of the function $f(x)={ x }^{ 3/5 }\left( 4-x \right) ,x\in { R }^{ + }\cup \left\{ 0 \right\}$ is _______