Skip to main content
Indietro

Precalculus Study Guide: Analysis of Graphs of Functions

Guida di studio - Note intelligenti

Appunti personalizzati basati sui tuoi materiali, ampliati con definizioni chiave, esempi e contesto.

Q1. Solve the following equation by completing the square:

Background

Topic: Quadratic Equations & Completing the Square

This question tests your ability to solve a quadratic equation by the method of completing the square, which is a fundamental algebraic technique used in Precalculus.

Key Terms and Formulas:

  • Quadratic equation:

  • Completing the square: Transforming into

  • Square root property: If , then

Step-by-Step Guidance

  1. Start by moving the constant term to the other side:

  2. To complete the square, take half of the coefficient of (which is ), square it, and add it to both sides:

  3. Add $16y^2 - 8y + 16 = 3 + 16$

  4. Rewrite the left side as a perfect square:

Try solving on your own before revealing the answer!

Final Answer:

After completing the square, you use the square root property to solve for .

This matches option d.

Q2. For the line segment bounded by the given endpoints, and , find the midpoint.

Background

Topic: Coordinate Geometry – Midpoint Formula

This question tests your understanding of how to find the midpoint of a line segment given two endpoints in the coordinate plane.

Key Terms and Formulas:

  • Midpoint formula:

  • Endpoints: and

Step-by-Step Guidance

  1. Identify the coordinates of the endpoints: and

  2. Apply the midpoint formula to the -coordinates:

  3. Apply the midpoint formula to the -coordinates:

  4. Write the midpoint as an ordered pair

Try solving on your own before revealing the answer!

Final Answer:

By calculating the averages, you find the midpoint is , which matches option b.

Q3. Solve: and also find domain of $f \circ g(x)$ where ,

Background

Topic: Function Composition and Domain

This question tests your ability to compose two functions and determine the domain of the resulting function.

Key Terms and Formulas:

  • Function composition:

  • Domain: Set of input values for which the function is defined

  • Square root function: is defined for

Step-by-Step Guidance

  1. Write as

  2. Substitute into :

  3. Determine the domain: Since , must be

  4. Express the domain in interval notation:

Try solving on your own before revealing the answer!

Final Answer: ; Domain:

The composition is and the domain is all .

This matches option b.

Q4. Use the standard graph of to transform it into the following function

Background

Topic: Transformations of Absolute Value Functions

This question tests your understanding of how to apply transformations (stretch, shift, translation) to the absolute value function.

Key Terms and Formulas:

  • Absolute value function:

  • Transformations:

  • Vertical stretch: ; Horizontal compression: ; Horizontal shift: ; Vertical shift:

Step-by-Step Guidance

  1. Identify the transformations: (vertical stretch), (horizontal compression), (horizontal shift), (vertical shift)

  2. Find the vertex: Set

  3. The graph is vertically stretched by $2\frac{3}{4}

  4. Compare the transformed graph to the options provided

Graph of f(x) = |x|Transformed absolute value graph with vertex at (-0.75, 0)Transformed absolute value graph with vertex at (-0.75, -3) and (0, 3)Transformed absolute value graph with vertex at (0.75, 3)Transformed absolute value graph with vertex at (-0.75, 3)

Try solving on your own before revealing the answer!

Final Answer: The correct graph is image_5

The vertex is at , matching the transformation .

Q5. Graph as a transformation of the square root function

Background

Topic: Transformations of Square Root Functions

This question tests your ability to graph a transformed square root function and recognize shifts and translations.

Key Terms and Formulas:

  • Square root function:

  • Transformation:

  • Horizontal shift:

Step-by-Step Guidance

  1. Set the inside of the square root to zero to find the starting point:

  2. The graph of is shifted right by $3f(x)$

  3. Compare the transformed graph to the options provided

Graph of f(x) and h(x) with vertical shiftGraph of f(x) and h(x) with vertical shift upGraph of f(x) and h(x) with horizontal shift leftGraph of f(x) and h(x) with horizontal shift right

Try solving on your own before revealing the answer!

Final Answer: The correct graph is image_9

The graph is shifted right by $3h(x) = \sqrt{2x - 6}$.

Q6. For the following function, sketch its graph:

Background

Topic: Graphing Square Root Functions

This question tests your ability to graph a square root function with a coefficient inside the radical.

Key Terms and Formulas:

  • Square root function:

  • Domain:

  • Transformation: Horizontal stretch/compression

Step-by-Step Guidance

  1. Set to find the starting point:

  2. For , increases as increases

  3. Compare the graph to the options provided

Graph of g(x) = sqrt(25x)Graph of g(x) = sqrt(25x)Graph of g(x) = sqrt(25x)Graph of g(x) = sqrt(25x)

Try solving on your own before revealing the answer!

Final Answer: The correct graph is image_13

The graph starts at and increases rapidly, matching the square root function with a large coefficient inside the radical.

Q7. Given the two functions and , find and identify the domain.

Background

Topic: Function Operations – Multiplication and Domain

This question tests your ability to multiply two functions and determine the domain of the resulting function.

Key Terms and Formulas:

  • Function multiplication:

  • Domain: Set of input values for which both functions are defined

Step-by-Step Guidance

  1. Write as

  2. Substitute the expressions:

  3. Expand the product:

  4. Simplify the expression and consider the domain (both functions are defined for all real numbers)

Try solving on your own before revealing the answer!

Final Answer: ; Domain:

Both functions are defined everywhere, so the domain is all real numbers.

This matches option c.

Q8. For the given one-to-one function, find the inverse function, , and verify that your equation is correct.

Background

Topic: Inverse Functions

This question tests your ability to find the inverse of a linear function and verify it by composition.

Key Terms and Formulas:

  • Inverse function:

  • To find the inverse, solve for

  • Verification:

Step-by-Step Guidance

  1. Write

  2. Solve for in terms of :

  3. Replace with to write the inverse:

  4. Verify by checking

Try solving on your own before revealing the answer!

Final Answer:

Composing and gives , confirming the inverse.

This matches option d.

Q9. Find and if and

Background

Topic: Inverse Functions and Composition

This question tests your ability to find the inverse of a composition of functions and the composition of their inverses.

Key Terms and Formulas:

  • Function composition:

  • Inverse of composition:

  • Inverse functions: ,

  • Composition of inverses:

Step-by-Step Guidance

  1. Find :

  2. To find , solve for

  3. Find and separately

  4. Compose

Try solving on your own before revealing the answer!

Final Answer: ,

Solving for in the composition and composing the inverses gives these results.

This matches option a.

Pearson Logo

Study Prep