1.

If x = - 1 and x =2 are exterme points of the function y=a `log x + bx^(2) + x`, then-A. `a=2,b= 1//2`B. `a=2,b=-1//2`C. `a=-2,b= 1//2`D. `a=- 2, b=- 1//2`

Answer» Correct Answer - 2
`(dy)/(dx) = (a)/(x) + 2 bx +1`
Since `x=-1` and `x=2` are extreme points so gy/dx at these points must be zero . So
`- a - 2b + 1 = 0 and a//2 + 4b + 1 = 0`
`rArr a+ 2b -1=0 and a+ 8b + 2=0`
`rArr a= 2, b=- 1//2`


Discussion

No Comment Found

Related InterviewSolutions