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Calculus help, I am trying to do this questions.. someone teach me please 10 points

Calculus help, I am trying to do this questions.. someone teach me please 10 points-example-1
User Iglo
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2 Answers

14 votes
14 votes

Answer:

Explanation:

Calculus help, I am trying to do this questions.. someone teach me please 10 points-example-1
Calculus help, I am trying to do this questions.. someone teach me please 10 points-example-2
User SmallB
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27 votes
27 votes

A bit late, but better than never.

24. For
x\\eq1, we have


(9x^2 - x - 8)/(x - 1) = ((x-1)(9x+8))/(x-1) = 9x+8

Then as
x approaches 1, we have


\displaystyle \lim_(x\to1) f(x) = \lim_(x\to1) (9x+8) = 17 \\eq 0

so the function is not continuous at
x=1. It is thus continuous on the interval union
(-\infty,0)\cup(0,\infty). You can also write this as "
x<0 or
x>0".

25. When
x approaches 2 from the left (when
x<2), we have


\displaystyle \lim_(x\to2^-) f(x) = \lim_(x\to2) (5-x) = 3

When
x approaches 2 from the right
(x>2), we have


\displaystyle \lim_(x\to2^+) f(x) = \lim_(x\to2) (2x-3) = 1

so the function is not continuous at
x=2. Thus it's continuous on
(-\infty,2)\cup(2,\infty), or "
x<2 or
x>2".

User Prancer
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