Question

What is the inverse for the function? y= 2x + 3

Answer 1

Y = 2x + 3

Let y = f(x), solving for the inverse function is solving for x

y = 2x + 3

2x + 3 = y

2x  = y - 3

x = (y - 3)/2

Recall that  y = f(x), that implies that x = f⁻¹( y)

x = (y - 3)/2,   substitute x = f⁻¹( y)

f⁻¹( y) = (y - 3)/2

if  f⁻¹( y) = (y - 3)/2, then:  Replace the y with x.

f⁻¹(x) = (x - 3)/2

Answer 2

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