$f(x)=x^3+p x^2+q x+10$ has a maximum at x = -3 and a minimum at x = 1. The values of p and q are: |
p = -3, q = -9 p = 3, q = 9 p = -3, q = 9 p = 3, q = -9 |
p = 3, q = -9 |
The correct answer is Option (4) → $p = 3, q = -9$ $f(x)=x^3+p x^2+q x+10$ It has maximum at $x=-3$ and a minimum at $x=1$ To find critical points, $f'(x)=0$ $⇒3x^2+2px+q=0$ and, $f'(-3)=0$ $⇒3(-3)^2+2p(-3)+q=0$ $⇒6p-q=27$ ...(1) $f'(1)=0$ $⇒3(1)+2p+q=0$ $⇒2p+q=-3$ ...(2) Solving both (1) and (2), we get $p=3$ and $q=-9$ |