How do you find the intercepts for F(x)=(x^2+x-12)/(x^2-4)F(x)=x2+x−12x2−4?
1 Answer
Feb 19, 2016
x= -4 , x = 3 , y=3
Explanation:
When any function crosses the x-axis , the corresponding y-coordinate will be zero. By letting y = 0 , we can find the x-intercept.
hence :
(x^2 + x - 12)/(x^2 - 4 ) = 0x2+x−12x2−4=0 now for this rational function to be zero . it can only be from the numerator as division by zero is undefined.
rArr x^2 + x - 12 = 0⇒x2+x−12=0
factor and solve.(x+ 4 )(x - 3 ) = 0 → x = - 4 , x = 3
Similarly , when the function crosses the y-axis , let x = 0.
rArr y =( -12)/-4 = 3 → y = 3 ⇒y=−12−4=3→y=3
