Exponential Functions Review

Which of the following attributes does the parent function, y = b^x, not exhibit?

• Domain: (-∞, ∞)
• Range: (0, ∞)
• y-intercept: (0, 1)
• Asymptote: y = 2

Which of the following is NOT a transformation that occurs when f(x) = 2^x is replaced by -2f(x+3) - 5?

• Reflected over the x-axis
• Vertically stretched by a factor of 2
• Moved to the left 3
• Moved up 5

A computer was purchased for $1,750 and depreciates at a value of 3/4 every year. Write an equation to represent this depreciation.

• y = 1750 (3/4)^t
• y = 1750 (1/4)^t
• y = 1312.5 (3/4)^t
• y = 1750 (3/4)^t/365

A culture of 4,500 bacteria quadruples every 7 hours. Write an exponential function to represent this growth.

• y = 4500(4)^t
• y = 4500(4)^t/7
• y = 4500(3)^t/7
• y = 4500(2)^t/7

Describe the transformations on y = 3(10^x-7) + 2

• Vertically compressed by 3, moved left 7, moved up 2
• Vertically compressed by 3, moved right 7, moved up 2
• Vertically stretched by 3, moved right 7, moved up 2
• Vertically stretched by 3, moved left 7, moved up 2

Write the domain and range of the following function:
y = 5^x+4 - 6

• Domain: all real numbers
  Range: y > -6
• Domain: all real numbers
  Range: y > 0
• Domain: all real numbers
  Range: y < 0
• Domain: x > -6
  Range: y > -4

Rewrite in logarithmic form: 6 = 2^x

• log₆2=x
• log₂6=x
• log_x2=6
• log_x6=2

A population triples every five years. If the starting population is 4500, write an equation to represent this growth.

• y = 4500(2)^t/5
• y = 4500(3)^t
• y = 4500(3)^t/5
• y = 4500(5)^t/3

Write the domain and range of the following function:
y = -4(3)^x

• Domain: all real numbers
  Range: (0, ∞)
• Domain: all real numbers
  Range: (-∞, 0)

What type of function is f(x)=2(1/7)^x ?

• Exponential Growth
• Linear
• Exponential Decay
• None of the Abovee