IndietroCollege Algebra Study Guide: Operations, Factoring, Equations, and Applications
Guida di studio - Note intelligenti
Appunti personalizzati basati sui tuoi materiali, ampliati con definizioni chiave, esempi e contesto.
Q1. (x^2 - 3x + 2) - (x - 4x^2)
Background
Topic: Polynomial Operations
This question tests your ability to subtract polynomials and combine like terms.
Key Terms and Formulas
Polynomial: An expression consisting of variables and coefficients, combined using addition, subtraction, and multiplication.
Like terms: Terms with the same variable raised to the same power.
Step-by-Step Guidance
Write both polynomials in standard form (descending powers of x).
Distribute the negative sign to each term in the second polynomial.
Combine like terms by adding or subtracting the coefficients of terms with the same degree.
Write the resulting polynomial in standard form.
Try solving on your own before revealing the answer!
Final Answer: 5x^2 - 4x + 2
After distributing the negative and combining like terms, you get .
Q2. (6r - 5)^2
Background
Topic: Expanding Binomials
This question tests your ability to expand the square of a binomial using the distributive property or the binomial formula.
Key Terms and Formulas
Binomial Square Formula:
Step-by-Step Guidance
Identify and in the expression .
Apply the binomial square formula: .
Calculate each term: , , and .
Combine the terms to write the expanded expression.
Try solving on your own before revealing the answer!
Final Answer: 36r^2 - 60r + 25
Expanding gives .
Q3. (t + 2)(3t^2 - t + 4)
Background
Topic: Multiplying Polynomials
This question tests your ability to multiply a binomial by a trinomial.
Key Terms and Formulas
Distributive Property:
Step-by-Step Guidance
Distribute each term in the binomial to each term in the trinomial .
Multiply by each term in the trinomial.
Multiply $2$ by each term in the trinomial.
Add the results together and combine like terms.
Try solving on your own before revealing the answer!
Final Answer: 3t^3 + 5t^2 + 2t + 8
After distributing and combining like terms, the result is .
Q4. \( \frac{2x^3 - 11x^2 + 28}{x - 5} \)
Background
Topic: Polynomial Division
This question tests your ability to divide a cubic polynomial by a linear binomial using either long division or synthetic division.
Key Terms and Formulas
Polynomial Division: Dividing one polynomial by another, often using long division or synthetic division.
Step-by-Step Guidance
Set up the division, identifying the divisor and the dividend .
If using synthetic division, use as the synthetic divisor.
Write the coefficients of the dividend in order, including zeros for missing terms.
Perform the synthetic division steps: bring down the first coefficient, multiply, add, and repeat for each column.
Try solving on your own before revealing the answer!
Final Answer: 2x^2 - x - 5 + \frac{3}{x-5}
After performing the division, the quotient is with a remainder of $3$.
Q5. Use synthetic division to perform: \( \frac{3x^3 + 4x^2 - 9x + 6}{x + 2} \)
Background
Topic: Synthetic Division
This question tests your ability to use synthetic division to divide a cubic polynomial by a linear binomial.
Key Terms and Formulas
Synthetic Division: A shortcut method for dividing a polynomial by a binomial of the form .
Step-by-Step Guidance
Set up synthetic division using (since the divisor is ).
List the coefficients: .
Carry out the synthetic division steps: bring down the first coefficient, multiply, add, and repeat.
Interpret the result as the coefficients of the quotient and the remainder.
Try solving on your own before revealing the answer!
Final Answer: 3x^2 - 2x - 5 + \frac{-4}{x+2}
The quotient is with a remainder of .
Q6. Factor completely: 6x^2 - 17x + 7
Background
Topic: Factoring Quadratic Polynomials
This question tests your ability to factor a quadratic trinomial into the product of two binomials.
Key Terms and Formulas
Factoring: Writing a polynomial as a product of its factors.
Quadratic trinomial: A polynomial of the form .
Step-by-Step Guidance
Identify , , .
Look for two numbers that multiply to and add to .
Rewrite the middle term using these two numbers and factor by grouping.
Factor out the greatest common factor from each group and write the final factored form.
Try solving on your own before revealing the answer!
Final Answer: (6x - 1)(x - 7)
The quadratic factors as .
Q7. Solve: |x + 4| = 7
Background
Topic: Absolute Value Equations
This question tests your ability to solve equations involving absolute values.
Key Terms and Formulas
Absolute Value: is the distance of from zero on the number line.
Solving : or
Step-by-Step Guidance
Set up two equations: and .
Solve each equation for .
Try solving on your own before revealing the answer!
Final Answer: x = 3, x = -11
There are two solutions: and .
Q8. Graph the quadratic function . Give the intercepts, vertex, axis, domain, range, and the largest open intervals of the domain over which the function is increasing or decreasing.
Background
Topic: Quadratic Functions and Graphing
This question tests your understanding of the properties of quadratic functions, including graphing, finding intercepts, vertex, axis of symmetry, domain, range, and intervals of increase/decrease.
Key Terms and Formulas
Vertex form:
Vertex:
Axis of symmetry:
Domain: All real numbers for quadratic functions.
Range: Depends on the direction the parabola opens.
Step-by-Step Guidance
Identify , , and in the quadratic function.
Find the vertex using and substitute back to find .
Find the y-intercept by evaluating .
Find the x-intercepts by solving .
Determine the axis of symmetry, domain, and range.
Describe the intervals where the function is increasing or decreasing.
Try solving on your own before revealing the answer!
Final Answer:
Vertex: Axis: y-intercept: x-intercepts: Domain: Range: Increasing on , decreasing on .