What is the domain of the function? f(x)=[tex]\frac{x-3}{2x^{2}+x-21 }[/tex] (−∞,3)∪(3,∞) (−∞,−3)∪(−3,72)∪(72,∞) (−∞,−72)∪(−72,∞) (−∞,−72)∪(−72,3)∪(3,∞)

What is the domain of the function fxtexfracx32x2x21 tex 33 337272 7272 727233 class=

Respuesta :

Answer:

(−∞,−7/2)∪(−7/2,3)∪(3,∞)

Step-by-step explanation:

(x-3)

----------------

2x^2 +x -21

First factor the denominator

(x-3)

----------------

( 2x +7) (x-3)

The domain is restricted when the denominator goes to zero

2x+7 =0    x-3 =0

2x = -7     x-3=0

x = -7/2    x =3

This two points are not in the domain

(−∞,−7/2)∪(−7/2,3)∪(3,∞)