ASAP PLZZZZZZZ

Use properties of limits to find the indicated limit. It may be necessary to rewrite an expression before limit properties can be applied

limx→1 
x3+5x2+3x−9x−1

a. 16
b.-16
c.0

Respuesta :

DeanR

I'm guessing what's really being asked is

[tex]\displaystyle \lim_{x \to 1} \dfrac{x^3 + 5x^2 + 3x -9}{x-1} [/tex]

Since x=1 is a root of the numerator, we can factor out x-1 which then will cancel with the denominator. Here's the long division; sorry about the lame formatting.

__ x^2 + 6x + 9

x-1 | x^3 + 5x^2 + 3x -9

___ x^3 - x^2

_______ 6x^2 + 3x

_______ 6x^2 - 6x

____________ 9x - 9

____________ 9x - 9

[tex]\quad[/tex]

[tex]\displaystyle \lim_{x \to 1} \dfrac{x^3 + 5x^2 + 3x -9}{x-1} [/tex]

[tex] = \displaystyle \lim_{x \to 1} \dfrac{(x-1)(x^2 + 6x + 9)}{x-1} [/tex]

[tex] = \displaystyle \lim_{x \to 1} x^2 + 6x + 9[/tex]

[tex] = 1^2 + 6(1)+9[/tex]

[tex] = 16[/tex]

Answer: 16

Choice a