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## Homework Statement

g(x)=√(5+x)-x

a) Write down D(g)

b) Solve the equation

√(5+x)-x=3

## Homework Equations

√(5+x)-x=3

## The Attempt at a Solution

a)

x∈ℝ: x>-5

b)[/B]

√(5+x)-x=3

√(5+x)=x+3

(5+x)=(x+3)^2

(5+x)=(x+3)(x+3)

(5+x)=x^2+6x+9

x^2+5x+4=0

(x+4)(x+1)

x=-4 or x=-1

√(5-4)--4=3

√(1)+4=3 False

√(5-1)--1=3

2+1=3 True

x=-1

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