Question

If `f(x)=0` is a quadratic equation such that `f(-pi)=f(pi)=0` and `f((pi)/(2))=-(3pi^(2))/(4)`, then `lim_(xto -pi^+) (f(x))/(sin(sinx))` is equal to
A. `-(3)/(2)pi`
B. `-(1)/(2)`
C. `(2pi)`
D. `(3)/(2)pi`

Answer 1

Correct Answer - C
Given `f(x)=x^(2)-pi^(2)`
`underset(xto-pi^+)lim(x^(2)-pi^(2))/(sin(sinx))=underset(hto0)lim((-pi+h)^(2)-pi^(2))/(sin(sin(-pi+h)))`
`=underset(hto0)lim(-2hpi+h^(2))/(-sin(sinh))`
`=underset(hto0)lim(h-2pi)/((-sin(sinh))/(sinh)xx(sinh)/(h))=2pi`

Comments

Ok