Chapter 7: Exp/Log Functions (Final Exam Review)

Find the inverse of y = 4x - 5

• f^-1(x) = -5 + 4x
• f^-1(x) = 4(x + 5)
• f^-1(x) = -4x + 5
• f^-1(x) = (x+5)/4

Find the inverse of (2, -1), (-3, -4), (-10, 5), (4, 1)

• (4, 1), (-10, 5), (-3, -4), (2, -1)
• (-2, 1), (3, 4), (10, -5), (-1, -4)
• (-1, 2), (-4, -3), (5, -10), (1, 4)
• (2, -3), (-10, 4), (-1, -4), (5, 1)

Which of the following is the formula for exponential growth?

• f(t) = a(1 - r)^t
• f(t) = a(1 + r)^t
• f(t) = a(1r)^t
• f(t) = a(-1)^t

Which of the following is the formula for exponential decay?

• f(t) = a(1 - r)^t
• f(t) = a(1 + r)^t
• f(t) = a(1r)^t
• f(t) = a(-1)^t

Determine whether the following function is exponential growth, exponential decay, or neither. Then determine the multiplier and rate of growth or decay.
f(x) = 4(1.4)^x

• Exponential growth; multiplier: 1.4; rate of growth: 0.4
• Exponential decay; multiplier: 1.4; rate of decay: 0.4
• Exponential growth; multiplier: 0.4; rate of growth: 1.4
• Neither exponential growth or decay

Determine whether the following function is exponential growth, exponential decay, or neither. Then determine the multiplier and rate of growth or decay.
f(x) = 0.5(5/6)^x

• Exponential growth; multiplier: 5/6; rate of growth: 1/6
• Exponential decay; multiplier: 5/6; rate of decay: 1/6
• Exponential decay; multiplier: 1/6; rate of decay: 5/6
• Neither exponential growth or decay

Determine whether the following function is exponential growth, exponential decay, or neither. Then determine the multiplier and rate of growth or decay.
f(x) = 1.2x²

• Exponential growth; multiplier: 1.2; rate of growth: 0.2
• Exponential decay; multiplier: 1.2; rate of decay: 0.2
• Exponential growth; multiplier: 0.2; rate of growth: 1.2
• Neither exponential growth or decay

A computer value starts at $4,000 and decreases by 8% each year. Write a function A(t) to represent the value of the computer as a function of t years.

• A(t) = 4,000(0.92)^t
• A(t) = 4,000(0.08)^t
• A(t) = 4,000(1.08)^t
• A(t) = 0.92(4,000)^t

What is the multiplier of the exponential function A(t) = 500(1+0.4)^t

• 0.4
• 1
• 500
• 1.40

The exponential function A(t) = 4,000(0.75)^t represents the value of a computer after t years. Find the value of the computer after 5 years.

• $15,000
• $949.22
• $3,000
• $3,776.35