Factor polynomials, perform polynomial arithmetic, understand the relationship between factors and zeros, and use the Remainder Theorem.
How can I study Polynomials and Factoring effectively?โพ
Start by reading the study notes and working through the examples on this page. Then use the flashcards to test your recall. Practice with the 5 problems provided, checking solutions as you go. Regular review and active practice are key to retention.
Is this Polynomials and Factoring study guide free?โพ
Yes โ all study notes, flashcards, and practice problems for Polynomials and Factoring on Study Mondo are 100% free. No account is needed to access the content.
What course covers Polynomials and Factoring?โพ
Polynomials and Factoring is part of the SAT Prep course on Study Mondo, specifically in the Passport to Advanced Math section. You can explore the full course for more related topics and practice resources.
Are there practice problems for Polynomials and Factoring?
x
n
+
anโ1โxnโ1+
โฏ+
a1โx+
a0โ
Degree: The highest power of the variable
Leading coefficient: The coefficient of the highest-degree term
Find two numbers that multiply to c and add to b.
Example: x2+7x+12=(x+3)(x+4)
5. Trinomial Factoring (ax2+bx+c, a๎ =1)
Use the AC method or trial and error.
Example: 2x2+7x+3=(2x+1)(x+3)
6. Sum and Difference of Cubes
a3+b3=(a+b)(a2โab+b2)a3โb3=(aโb)(a
7. Factor by Grouping
x3+3x2+2x+6=x2(x+3)+2(x+3)=(x2+2)(x+3)
Polynomial Operations
Addition/Subtraction
Combine like terms (same variable, same exponent).
Multiplication
Use FOIL for binomials, or distribute each term.
(2x+3)(xโ4)=2x2โ8x+3xโ12=2x2โ5xโ12
Division
Polynomial long division or synthetic division (for dividing by xโc).
Remainder Theorem
When polynomial P(x) is divided by (xโc), the remainder is P(c).
Example: If P(x)=x3โ2x+1, the remainder when divided by (xโ3) is:
P(3)=27โ6+1=22
Factor Theorem
(xโc) is a factor of P(x) if and only if P(c)=0.
Example: Is (xโ2) a factor of x3โ4x2+x+6?
P(2)=8โ16+2+6=0 โ Yes!
SAT Question Types
Type 1: Factor a Polynomial
"Factor x2โ5xโ6" โ (xโ6)(x+1)
Type 2: Find Zeros from Factored Form
"If f(x)=(xโ2)(x+3)(xโ5), what are the zeros?" โ x=2,โ3,5
Type 3: Polynomial Division
"What is the remainder when x3+2xโ5 is divided by xโ1?"
P(1)=1+2โ5=โ2 (use the Remainder Theorem!)
Type 4: Equivalent Expressions
"Which expression is equivalent to (x+2)3?"
=x3+3(x2)(2)+3(x)(4)+8=x3+6x2+12x+8
Common SAT Mistakes
Sign errors when factoring โ double-check by FOILing your answer
Forgetting the GCF before trying other methods
Confusing (x+3)2 with x2+9 โ it's x2+6x+9!
Not using the Remainder Theorem โ much faster than long division
Dropping terms when subtracting polynomials โ distribute the negative sign
3x2โ12=3(x2โ4)
Step 2: Recognize the difference of squares:
3(x2โ4)=3(x+2)(xโ2)
Answer:3(x+2)(xโ2)
Key: Always look for a GCF first!
2Problem 2medium
โ Question:
Factor: 2x2+7x+3
๐ก Show Solution
AC Method:aโ c=2โ 3=6. Find two numbers that multiply to 6 and add to 7: 6 and 1.
Rewrite middle term:2x2+6x+x+3
Factor by grouping:2x(x+3)+1(x+3)(2x+1
Check:(2x+1)(x+3)=2x2+ โ
Answer:(2x+1)(x+3)
3Problem 3medium
โ Question:
What is the remainder when P(x)=2x3โx2+3xโ7 is divided by (xโ2)?
๐ก Show Solution
Use the Remainder Theorem: The remainder when P(x) is divided by (xโc) is P(c).
Here :
4Problem 4hard
โ Question:
If f(x)=x3โ6x2+11xโ6 and f(1)=0, factor f(x) completely.
๐ก Show Solution
Step 1: Since f(1)=0, by the Factor Theorem, (xโ1) is a factor.
Step 2: Divide by using synthetic division:
5Problem 5expert
โ Question:
Which polynomial has zeros at x=โ1, x=2, and x=4, and passes through the point (0,โ16)?
๐ก Show Solution
Step 1: Write the general form using the zeros:
f(x)=a(x+1)(xโ2)(xโ
โพ
Yes, this page includes 5 practice problems with detailed solutions. Each problem includes a step-by-step explanation to help you understand the approach.
2
2
+
ab+
b2)
)
(
x
+
3)
6
x
+
x+
3=
2x2+
7x+
3
c=2
P(2)=2(2)3โ(2)2+3(2)โ7
=2(8)โ4+6โ7
=16โ4+6โ7
=11
Answer: The remainder is 11.
SAT Tip: The Remainder Theorem saves enormous time compared to polynomial long division!
x3โ6x2+11xโ6
(xโ1)
1โฃ1โ611โ6โฃ1โ561โ560
Quotient: x2โ5x+6
Step 3: Factor the quadratic:
x2โ5x+6=(xโ2)(xโ3)
Answer:f(x)=(xโ1)(xโ2)(xโ3)
The zeros are x=1,2,3.
4
)
Step 2: Use the point (0,โ16) to find a:
f(0)=a(0+1)(0โ2)(0โ4)=a(1)(โ2)(โ4)=8aโ16=8aa=โ2
Step 3: Write the final polynomial:
f(x)=โ2(x+1)(xโ2)(xโ4)