The area bounded by $y=x^2-3$ and $y=kx+2$ is the least. Then $k$ is
Step-by-Step Solution
Key Concept: Area between parabola and line depends on the chord length; minimize w.r.t. $k$
Area $=\frac{(\Delta)^{3/2}}{6a}$ where $\Delta=$ discriminant$=k^2+20$. Minimum when $k=0$.
Correct Answer: 4