Math Problem Statement

Find the domain and range

  1. y = - 2 ^ (5x - 1)

  2. y = 5 ^ (3x + 1) - 7

  3. y = - 7 ^ (2x - 3) + 5

Solution

Let's analyze each function individually to determine its domain and range:

1. y=2(5x1)y = -2^{(5x - 1)}

  • Domain: Exponential functions are defined for all real numbers. Therefore, the domain is: Domain: (,)\text{Domain: } (-\infty, \infty)

  • Range: The function 2(5x1)2^{(5x - 1)} is an exponential function that grows larger as xx increases and approaches 0 as xx decreases. Since the base of the exponential is positive and the coefficient is negative, the function will always be negative. The output values will approach 0 from below, but will never reach it.

    Range: (,0)\text{Range: } (-\infty, 0)


2. y=5(3x+1)7y = 5^{(3x + 1)} - 7

  • Domain: Again, exponential functions are defined for all real numbers. Therefore, the domain is: Domain: (,)\text{Domain: } (-\infty, \infty)

  • Range: The base function 5(3x+1)5^{(3x + 1)} is always positive and grows larger as xx increases. Subtracting 7 shifts the entire function down by 7 units. The minimum value of yy occurs when xx \to -\infty, where 5(3x+1)05^{(3x + 1)} \to 0. Therefore, the function will approach 7-7 but never reach it, and it will increase without bound as xx \to \infty.

    Range: (7,)\text{Range: } (-7, \infty)


3. y=7(2x3)+5y = -7^{(2x - 3)} + 5

  • Domain: Similar to the other cases, exponential functions are defined for all real numbers. Therefore, the domain is: Domain: (,)\text{Domain: } (-\infty, \infty)

  • Range: The base function 7(2x3)7^{(2x - 3)} is always positive and grows as xx increases. The negative sign flips the function, and adding 5 shifts the function upward by 5 units. The largest value of yy occurs when 7(2x3)07^{(2x - 3)} \to 0, which gives y=5y = 5. As xx \to \infty, 7(2x3)7^{(2x - 3)} becomes very large, and yy decreases without bound.

    Range: (,5)\text{Range: } (-\infty, 5)


Summary:

  1. y=2(5x1)y = -2^{(5x - 1)}

    • Domain: (,)(-\infty, \infty)
    • Range: (,0)(-\infty, 0)
  2. y=5(3x+1)7y = 5^{(3x + 1)} - 7

    • Domain: (,)(-\infty, \infty)
    • Range: (7,)(-7, \infty)
  3. y=7(2x3)+5y = -7^{(2x - 3)} + 5

    • Domain: (,)(-\infty, \infty)
    • Range: (,5)(-\infty, 5)

Do you have any questions or would you like further details on any part of this?

Here are five related questions you might explore:

  1. How does the base of an exponential function affect its growth rate?
  2. How would the domain and range change if the base were negative?
  3. What happens to the range if the exponent contains an absolute value term?
  4. How would the graph of these functions look, and what are the key features?
  5. How do transformations (like vertical shifts) affect the domain and range?

Tip: When working with exponential functions, keep in mind that any negative exponent will result in a reciprocal, making the function approach zero as xx decreases.

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Math Problem Analysis

Mathematical Concepts

Exponential Functions
Domain and Range
Transformations in Functions

Formulas

y = a^(bx + c) + d
Domain of exponential functions: (-∞, ∞)
Range of exponential functions depends on vertical shifts and reflections

Theorems

Exponential Growth and Decay Theorem
Rules of function transformations (shifts, reflections, and stretching)

Suitable Grade Level

Grades 10-12