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What are the restrictions on the domain for the following rational expression?

What are the restrictions on the domain for the following rational expression?-example-1
User MattJHoughton
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1 Answer

8 votes
8 votes

Answer:

x <> -3, 8

Explanation:

x² - 5x - 24 (the denominator of the fraction) must not be 0, because n/0 is not defined for any n.

since this is a quadratic equation, it must have 2 solutions.

therefore, the second answer must be right.

let's check.

a quadratic equation

ax² + bx + c = 0

has the solutions

x = (-b ± sqrt(b² - 4ac))/(2a)

in our case

x = (5 ± sqrt((-5)² - 4×1×-24))/(2×1) =

= (5 ± sqrt(25 + 96))/2 = (5 ± sqrt(121))/2 =

= (5 ± 11)/2

x1 = (5 + 11)/2 = 16/2 = 8

x2 = (5 - 11)/2 = -6/2 = -3

correct.

User Fathah Rehman P
by
3.3k points