Core Connections Integrated II, 2015
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Core Connections Integrated II, 2015 View details
4. Section 9.4
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Exercise 132 Page 530

Practice makes perfect
a Before we can find the inverse of the given function, we need to replace f(x) with y.
f(x)=2x+3 ⇔ y=2x+3Now, to algebraically determine the inverse of the given equation we exchange x and y and solve for y. Given Equation & Inverse Equation y=2 x+3 & x=2 y+3 The result of isolating y in the new equation will be the inverse of the given function.
x=2y+3
Solve for y
x-3=2y
2y=x-3
y=x-3/2
Finally, we write the inverse of the given function in function notation by replacing y with f^(- 1)(x) in our new equation. f^(- 1)(x)=x-3/2
b Before we can find the inverse of the given function we need to replace g(x) with y.
g(x)=x-5/4 ⇔ y=x-5/4Now, to algebraically determine the inverse of the given equation we exchange x and y and solve for y. Given Equation & Inverse Equation y=x-5/4 & x=y-5/4 The result of isolating y in the new equation will be the inverse of the given function.
x=y-5/4
Solve for y
4x=y-5
4x+5=y
y= 4x+5
Finally, we write the inverse of the given function in function notation by replacing y with g^(- 1)(x) in our new equation. g^(- 1)(x)=4x+5