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Pls help!!!!1! domain problem

Pls help!!!!1! domain problem-example-1
User Phoenix Mu
by
5.5k points

1 Answer

1 vote

Answer:

x ∈ R, x ≠ 1

Explanation:

f(g(x))

= f(
(4)/(x-2) )

=
(1)/((4)/(x-2)+4 )

=
(1)/((4+4(x-2))/(x-2) )

=
(1)/((4+4x-8)/(x-2) )

=
(x-2)/(4x-4)

The denominator of f(g(x)) cannot be zero as this would make f(g(x)) undefined. Equating the denominator to zero and solving gives the value that x cannot be, that is

4x - 4 = 0 ⇒ 4x = 4 ⇒ x = 1 ← excluded value

Domain : x ∈ R, x ≠ 1, that is

(- ∞, 1) ∪ (1, ∞ ) ← in interval notation

User Caillou
by
5.3k points
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