Question

The points at which the function $f\left(x\right)=\frac{x+1}{x^2+x-12}$ is discontinuous, are

• A. –3, 4
• B. 3, –4
• C. –1,–3, 4
• D. –1, 3, 4

Answer 1

The correct option is B 3, –4

$f\left(x\right)=\frac{x+1}{(x-3)(x+4)}$ is discontinuous if

$(x-3)(x+4)=0$

$x=3,x=-4$

$atx=3$ , $f\left(x\right)=\infty$

and $atx=-4,f(x)=\infty$

Hence, given function is not contentious at points $3,-4.$