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If a(x)=3x+1 and b(x)=

√(x - 4)
what is the domain of (b○a)(x)?​

User Cefn
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1 Answer

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Answer: Domain: x

Explanation: First, we must write the equation for (b ° a)(x).

Write b(x).

b(x) = √(x - 4)

Substitute x in b(x) for a(x) to get (b ° a)(x).

(b ° a)(x) = √(3x + 1 - 4)

Simplify the right side of the equation.

(b ° a)(x) = √(3x - 3)

To find the domain, write this function as an inequality greater than or equal to 0.

√(3x - 3) ≥ 0

Raise both sides to the power of 2.

3x - 3 ≥ 0

Add 3 to both sides.

3x ≥ 3

Divide both sides by three.

x ≥ 1

Write this inequality as your domain in set notation.

Domain: x
User Jenna Kwon
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