Question:
Let $A(4,-4)$ and $B(9,6)$ be points on the parabola, $\mathrm{y}^{2}+4 \mathrm{x}$. Let $\mathrm{C}$ be chosen on the arc $\mathrm{AOB}$ of the parabola, where $O$ is the origin, such that the area of $\triangle A C B$ is maximum. Then, the area (in sq. units) of $\triangle \mathrm{ACB}$, is:
Correct Option: , 4
Solution:
Area $=5\left|\mathrm{t}^{2}-\mathrm{t}-6\right|=5\left|\left(\mathrm{t}-\frac{1}{2}\right)^{2}-\frac{25}{4}\right|$
is maximum if $\mathrm{t}=\frac{1}{2}$