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Part 1: Polynomial Basics
Polynomials & Factoring
Part 1 of 7 โ Polynomial Basics
What is a Polynomial?
A polynomial is an expression with one or more terms: anโxn+anโ1โxnโ1+โฏ+a1โx+a0โ
- Degree: highest power of x (e.g., 3x4+2xโ1 has degree 4)
- Leading coefficient: coefficient of the highest-degree term
- Constant term: the term with no variable (a)
Adding & Subtracting Polynomials
Combine like terms (same variable and exponent):
(3x2+5xโ2)+(x2
(3x2+5xโ2)โ(x
Subtraction trap: distribute the negative sign to ALL terms in the second polynomial!
Multiplying Polynomials
Use distribution (FOIL for binomials):
(2x+3)(xโ4)=2x2โ8x
Worked Example 1 โ Multiplying Three Factors
Expand (x+1)(xโ3)(x+2).
| Step | Work |
|---|
| First two factors | (x+1)(xโ3)=x2โ2x |
Worked Example 2 โ Subtraction Trap
Simplify (5x3โx2+4)โ(3x.
| Step | Work |
|---|
| Distribute negative | 5x3โx2+4โ3 |
Polynomial Operations ๐ฏ
Special Products to Memorize
| Pattern | Expansion |
|---|
| (a+b)2 | a2+ |
Special Products & Degree ๐ฏ
Identify the Property ๐
For each expression, identify what type of operation or pattern it represents.
Key Takeaways โ Part 1
| Concept | Key Point |
|---|
| Degree | Highest exponent (not first term!) |
| Subtraction | Distribute negative to ALL terms |
| (a+b)2 | a (don't forget middle term) |
Part 2: Factoring Techniques
Polynomials & Factoring
Part 2 of 7 โ Factoring Techniques
GCF Factoring
Always look for a Greatest Common Factor first:
6x3+9x2=3x
Part 3: Special Products
Polynomials & Factoring
Part 3 of 7 โ Polynomial Division
Long Division
Divide x3+2x2โ5x+6 by :
Part 4: Polynomial Division
Polynomials & Factoring
Part 4 of 7 โ Zeros, Roots, and the Factor Theorem
Zeros = Roots = x-intercepts
These terms all mean the same thing: the values of x where f(x)=0.
If f(x, the zeros are .
Part 5: Zeros & Roots
Polynomials & Factoring
Part 5 of 7 โ Rational Expressions
Simplifying Rational Expressions
A rational expression is a fraction with polynomials:
x
Part 6: Problem-Solving Workshop
Polynomials & Factoring
Part 6 of 7 โ Polynomial Graphs and Transformations
Reading Polynomial Graphs
From a graph, you can determine:
- Zeros: where the curve crosses/touches the x-axis
- y-intercept: where the curve crosses the y-axis (the constant term)
- Degree: count the number of turns + 1 (approximately)
- Leading coefficient sign: from end behavior
Transformations
For f(x)=x3:
| Transformation | Equation | Effect |
|---|
| Vertical shift up |
Part 7: Review & Applications
Polynomials & Factoring
Part 7 of 7 โ Review & Advanced SAT Problems
Factoring Decision Tree
- GCF? Always check first
- Two terms? โ Difference of squares (a2โb2) or sum/difference of cubes
- Three terms? โ Trinomial factoring or completing the square
- Four terms? โ Factor by grouping
Factor by Grouping
:
0โ
โ
3x+
7)=
4x2+
2x+
5
2
โ
3x+
7)=
3x2+
5xโ
2โ
x2+
3xโ
7=
2x2+
8xโ
9
+
3xโ
12=
2x2โ
5xโ
12
โ
3
| Multiply by third | (x2โ2xโ3)(x+2) |
| Distribute x | x3โ2x2โ3x |
| Distribute 2 | 2x2โ4xโ6 |
| Combine | x3โ2x2+2x2โ3xโ4xโ6=x3โ7xโ6 |
3
+
2x2โ
x+
1)
x3
โ
2x2+
xโ
1
| Combine x3 | 2x3 |
| Combine x2 | โ3x2 |
| Result | 2x3โ3x2+x+3 |
2ab+
b2
| (aโb)2 | a2โ2ab+b2 |
| (a+b)(aโb) | a2โb2 |
| (a+b)3 | a3+3a2b+3ab2+b3 |
Worked Example 3 โ Using Special Products
Expand (3xโ2)2.
| Step | Work |
|---|
| Apply (aโb)2 | (3x)2โ2(3x)(2)+(2)2 |
| Simplify | 9x2โ12x+4 |
โ ๏ธ Common mistake: (3xโ2)2๎ =9x2โ4. You must include the middle term!
Degree of a Product
The degree of a product equals the sum of the degrees.
(2x3+1)(x2โ5x)โdegreeย 3+2=5
2
+
2ab+
b2
| (a+b)(aโb) | a2โb2 |
| Degree of product | Sum of degrees |
- Combine like terms as the final step after every operation
- FOIL is just distribution for two binomials โ use full distribution for larger products
- Special products save time and reduce errors on the SAT
2
(
2
x
+
3)
Difference of Squares
a2โb2=(a+b)(aโb)
Example: x2โ49=(x+7)(xโ7)
Tricky example: 4x2โ25=(2x)2โ52=(2x+5)(2xโ5)
Perfect Square Trinomials
a2+2ab+b2=(a+b)2
a2โ2ab+b2=(aโb)
How to recognize: first and last terms are perfect squares, middle term is ยฑ2รfirstโรlastโ.
x2+10x+25=(x+5)2 because 2(x)(5)=10x โ
Sum/Difference of Cubes (Rare on SAT)
a3+b3=(a+b)(a2โab+b2)
a3โb3=(aโb)(a
Worked Example 1 โ Multi-Step Factoring
Factor completely: 2x3โ18x.
| Step | Work |
|---|
| GCF | 2x(x2โ9) |
| Difference of squares | 2x(x+3)(xโ3) |
Worked Example 2 โ Recognizing Perfect Squares
Is 9x2โ30x+25 a perfect square trinomial?
| Check | Result |
|---|
| First term: (3x)2? | Yes โ |
| Last term: 52? | Yes โ |
| Middle: 2(3x)(5)=30x? | Yes โ |
| Factor | (3xโ5)2 |
Factoring Trinomials: ax2+bx+c
When a=1: Find two numbers that multiply to c and add to b.
x2+7x+12: numbers that multiply to 12 and add to 7? โ 3 and .
=(x+3)(x+4)
When a๎ =1: Use the AC method.
Worked Example 3 โ AC Method
Factor 6x2+11xโ10.
| Step | Work |
|---|
| aโ
c | 6ร(โ10)=โ60 |
| Find pair: product , sum |
Worked Example 4 โ Signs Guide
| If c>0, b>0 | Both factors positive | (x+?)(x+?) |
|---|
| If , |
What Factoring Method? ๐
Choose the best factoring technique for each expression.
Key Takeaways โ Part 2
| Method | When to Use | Example |
|---|
| GCF | Always check first | 6x3+9x2=3x2(2x+3) |
| Diff. of squares | a2โb2 | x2 |
| Perfect square | a2ยฑ2ab+b2 | x |
| Trinomial (a=1) | Find pair: product c, sum b | x |
| AC method (a๎ =1) | Product ac, sum b, then group | 6x |
- "Factor completely" = keep going until nothing else factors
- a2+b2 does NOT factor over the reals
- Signs of b and c tell you the signs of the factor pair
xโ1
- x3รทx=x2. Multiply: x2(xโ1)=x3โx2. Subtract: 3x2โ5x
- 3x2รทx=3x. Multiply: 3x(xโ1)=. Subtract:
- โ2xรทx=โ2. Multiply: โ2(xโ1)=โ2x+2. Subtract:
Result: x2+3xโ2 remainder 4.
Synthetic Division (Faster!)
For dividing by (xโc): write the coefficients, bring down, multiply, add.
Dividing x3+2x2โ5x+6 by (xโ1):
Result: x2+3xโ2 with remainder 4.
The Remainder Theorem
The remainder when f(x) is divided by (xโc) equals f(c).
Check: f(1)=1+2โ5+6=4 โ
Worked Example 1 โ Missing Term Trap
Divide x3โ8 by (xโ2).
| Step | Work |
|---|
| Include 0 placeholders | Coefficients: 1,0,0,โ8 |
| Synthetic with c=2 | Bring down 1 โ 1โ
2=2 โ 0+2=2 โ 2โ
2=4 โ 0+4=4 โ 4โ
2=8 โ โ8+8=0 |
| Result | x2+2x+4, remainder 0 |
So x3โ8=(xโ2)(x2+2x+4) โ this is the difference of cubes formula!
Worked Example 2 โ Using Remainder Theorem Strategically
Is (x+2) a factor of 2x3+x2โ7x+2?
| Step | Work |
|---|
| (x+2)=(xโ(โ2)), so c=โ2 | |
| Evaluate f(โ2) | 2(โ8)+(4)โ7(โ2)+2 |
| Simplify | โ16+4+14+2=4 |
| Remainder | 4๎ =0, so NO โ not a factor |
Writing the Result of Division
d(x)f(x)โ=q(x)+d(x)rโ
Example: x+1x2+3x+5โ=x
This form appears on the SAT! They may ask "what is the remainder" or "rewrite the expression."
Worked Example 3
Rewrite xโ1x2โ4x+7โ in quotient-remainder form.
| Step | Work |
|---|
| Divide | f(1)=1โ4+7=4 โ remainder is 4 |
| Synthetic: |
SAT Shortcut: Remainder without Division
To find just the remainder of f(x)รท(xโc), simply compute f(c). No division needed!
Division Applications ๐ฏ
Remainder Theorem Quick Check ๐
Find the remainder without doing long division.
Key Takeaways โ Part 3
| Tool | Purpose | Speed |
|---|
| Long division | Any divisor | Slow |
| Synthetic division | Divisor (xโc) only | Fast |
| Remainder Theorem | Find remainder only | Fastest |
| Factor Theorem | Check if factor | Fastest |
- Remainder Theorem: f(x)รท(xโc) โ remainder =f(c)
- Factor Theorem: (xโc) is a factor iff f(c)=0
- Include 0 coefficients for missing terms (e.g., x3โ8 โ 1,0,0,โ8)
- Division result: f(x)=d(x)โ
q(x)+r
)
=
(xโ
2)(x+
5)(xโ
1)
x=2,โ5,1 Multiplicity
The multiplicity of a zero is how many times its factor appears.
f(x)=(xโ3)2(x+1):
- x=3 has multiplicity 2 (graph touches x-axis and bounces)
- x=โ1 has multiplicity 1 (graph crosses x-axis)
End Behavior
| Degree | Leading Coeff. | Left End | Right End |
|---|
| Even | Positive | โ | โ |
| Even | Negative | โ | โ |
| Odd | Positive | โ | โ |
| Odd | Negative | โ | โ |
SAT Connection
The SAT asks: "How many x-intercepts does the graph of f(x)=x3โ4x have?"
Factor: x(x2โ4)=x(xโ2)(x+2). Three distinct factors โ 3 x-intercepts.
Worked Example 1 โ Building a Polynomial from Zeros
Find a polynomial with zeros at x=โ1,2,5 and leading coefficient 3.
| Step | Work |
|---|
| Write factors | (x+1)(xโ2)(xโ5) |
| Apply leading coeff. | 3(x+1)(xโ2)(xโ5) |
Worked Example 2 โ Finding a from a Point
f(x)=a(xโ1)(x+3) passes through (2,10). Find a.
| Step | Work |
|---|
| Substitute (2,10) | 10=a(2โ1)(2+3) |
| Simplify | 10=a(1)(5)=5a |
| Solve | a=2 |
| Answer | f(x)=2(xโ1)(x+3) |
Zeros & End Behavior ๐ฏ
Multiplicity and Graph Behavior
| Multiplicity | Graph at that zero | Example |
|---|
| 1 (odd) | Crosses x-axis | f(x)=xโ2 at x=2 |
| 2 (even) | Touches and bounces | f(x)=(xโ2)2 at x=2 |
| 3 (odd) | Crosses with inflection | f(x)=(xโ2)3 at x=2 |
Worked Example 3 โ Degree from Graph
A graph crosses the x-axis at x=โ3 and x=4, and bounces at x=1. Both ends point downward. What is the minimum degree?
| Zero | Min. multiplicity |
|---|
| x=โ3 (crosses) | 1 |
| x=1 (bounces) | 2 |
| x=4 (crosses) | 1 |
Both ends down โ even degree, negative leading coefficient โ (degree 4 is even).
Worked Example 4 โ Number of Real Zeros
f(x)=x4โ5x2+4. How many x-intercepts?
| Step | Work |
|---|
| Let u=x2 | u2โ |
Match the Graph Feature ๐
What does each piece of information tell you?
Key Takeaways โ Part 4
| Concept | Key Rule |
|---|
| Zeros from factors | (xโr) โ zero at x=r |
| Even multiplicity | Graph bounces at zero |
| Odd multiplicity | Graph crosses at zero |
| End behavior | Degree (even/odd) + sign of leading coeff. |
| Max turning points | Degree minus 1 |
| Build polynomial | f(x)=a(xโr1โ)(xโr |
- Given zeros + one point โ find a by substitution
- Number of real zeros โค degree of polynomial
- The SAT often shows a graph and asks for the equation โ read zeros + end behavior first
2
+
5
x
+
6
x2โ9
โ
=
(x+2)(x+3)(x+3)(xโ3)โ=
x+2xโ3โ(x๎ =
โ3)
Steps: Factor numerator and denominator, then cancel common factors.
Multiplying & Dividing
Multiply: Factor, cancel, then multiply what remains.
x+1x2โ4โโ
xโ2x+1โ=x+1(x+2)(xโ2)โโ
xโ2x+1โ=x+2
Divide: Flip the second fraction and multiply.
Adding & Subtracting
Find a common denominator:
x+12โ+xโ13โ=(x+1)(xโ1)2(xโ1)+3(x+1)โ=x2โ15x+1โ
Undefined Values (Domain Restrictions)
A rational expression is undefined when the denominator equals zero. The SAT asks: "What value of x makes the expression undefined?"
Worked Example 1 โ Multi-step Simplification
Simplify x2โxโ22x2โ8โ.
| Step | Work |
|---|
| Factor numerator | 2(x2โ4)=2(x+2)(xโ2) |
| Factor denominator | (xโ2)(x+1) |
| Cancel (xโ2) | x+12(x+2)โ, |
Worked Example 2 โ Subtracting with LCD
x+3xโโxโ12โ
| Step | Work |
|---|
| LCD | (x+3)(xโ1) |
| Rewrite | (x+3)(xโ1)x(xโ1)โ2(x+3)โ |
| Expand | (x+3)(xโ1)x |
Rational Expressions ๐ฏ
Complex Fractions
A complex fraction has a fraction in the numerator, denominator, or both:
x1โโy1โx1โ+y1โโ
Strategy: Multiply the top and bottom by the LCD of all the little fractions.
Worked Example 3 โ Simplifying a Complex Fraction
Simplify x1โ+3.
| Step | Work |
|---|
| LCD of inner fractions | 3x |
| Multiply top and bottom by 3x | |
Common SAT Trap โ Canceling Terms vs. Factors
| Expression | Can you cancel? | Why? |
|---|
| (x+2)(x+2)(xโ3)โ | โ
Yes | is a of both |
Rule: You can only cancel common factors โ never individual terms.
Advanced Rational Expressions ๐ฏ
Simplification Check ๐
Is each simplification valid?
Key Takeaways โ Part 5
| Operation | Procedure |
|---|
| Simplify | Factor top & bottom โ cancel common factors |
| Multiply | Factor all โ cancel across โ multiply |
| Divide | Flip 2nd fraction โ multiply |
| Add/Subtract | Find LCD โ combine numerators |
| Complex fraction | Multiply top & bottom by LCD of inner fractions |
| Common Trap | Fix |
|---|
| Canceling terms (x+5x+2โ) | Only cancel factors |
| Forgetting restrictions | State x๎ = (zeros of original denominator) |
| Sign errors in subtraction | Distribute the minus to ALL terms |
- Partial fractions (splitting one fraction into two) appear on harder SAT problems โ reverse the adding process
| Horizontal shift right h | f(xโh) | Graph moves right |
| Vertical stretch by a | af(x) | Taller/narrower |
| Reflection over x-axis | โf(x) | Flip upside down |
| Reflection over y-axis | f(โx) | Flip left-right |
SAT Graph Reading Strategy
When the SAT shows a polynomial graph and asks for the equation:
- Read the x-intercepts โ write factors
- Check end behavior โ determine sign of leading coefficient
- Check one more point (often the y-intercept) โ determine the leading coefficient
Worked Example 1 โ From Graph to Equation
A graph crosses at x=โ1 and x=4, bounces at x=2, and passes through (0,โ16). Find the equation.
| Step | Work |
|---|
| Write factors | a(x+1)(xโ4)(xโ2)2 |
| Use (0,โ16) | a(1)(โ4)(4)=โ16a=โ16 |
| Solve | a=1 |
| Answer | f(x)=(x+1)(xโ4)(xโ2)2 |
Worked Example 2 โ Transformation Chain
If f(x)=x3, describe the graph of g(x)=โ2(x+1)3+5.
| Transformation | Rule | Effect |
|---|
| (x+1)3 | f(xโh) with h=โ1 | Shift left 1 |
| 2(โฏ) | af(x) with a=2 | Vertical stretch by 2 |
| โ(โฏ) | โf(x) | Reflect over x-axis |
| +5 | f(x)+k | Shift up 5 |
The inflection point moves from (0,0) to (โ1,5).
Matching Equations to Graphs โ Decision Framework
On the SAT, you'll often see four equation choices and one graph (or vice versa). Here's how to eliminate quickly:
| Check | What it tells you | How to read it |
|---|
| End behavior | Degree (even/odd) + sign | Both ends same = even; opposite = odd |
| x-intercepts | Factors and their multiplicity | Crosses = odd mult.; bounces = even |
| y-intercept | Constant term | Plug x=0 into each answer choice |
| Number of turns | Approximate degree | Turns โค degree โ 1 |
Worked Example 3 โ Elimination by y-intercept
Which polynomial has y-intercept โ6 and zeros at x=1,2,3?
| Option | y-int (plug x=0) | Match? |
|---|
| (xโ1)(xโ2)(xโ |
Answer: (xโ1)(xโ2)(xโ3) โ no extra coefficient needed.
Inside vs. Outside โ Transformation Direction
A common SAT trap: shifts inside the function go the opposite direction.
| Written | Direction |
|---|
| f(xโ3) | Right 3 |
| f(x+3) | Left 3 |
|
Memory trick: Inside is "opposite" โ outside is "obvious."
Graphs & Transformations ๐ฏ
Transformation Identifier ๐
What transformation does each change represent?
Key Takeaways โ Part 6
| Skill | Strategy |
|---|
| Graph โ Equation | Read zeros, end behavior, y-intercept |
| Equation โ Graph | Plot zeros, check multiplicity, draw end behavior |
| Transformations | Inside = horizontal (opposite); outside = vertical |
| Elimination | Plug x=0 into choices to match y-intercept |
| Transformation | Direction Rule |
|---|
| f(xโh) | Right h (opposite sign) |
| f(x+h) | Left h (opposite sign) |
| f(x)+k | Up k (same sign) |
| af(x), a>1 | Vertical stretch |
| โf(x) | Reflect over x-axis |
- On the SAT, always check the y-intercept โ it's the fastest way to narrow four answer choices down to one
x3+3x2+2x+6
- Group: (x3+3x2)+(2x+6)
- Factor each group: x2(x+3)+2(x+3)
- Factor the common binomial: (x2+2)(x+3)
Special SAT Pattern: Disguised Quadratics
x4โ5x2+4: let u=x2:
u2โ5u+4=(uโ1)(uโ4)=(x2โ1)(x2โ4)=(x+1)(xโ1)(x+2)(xโ2)
This technique works whenever you see ax2n+bxn+c.
Worked Example 1 โ Multi-layer Factoring
Factor completely: 3x3โ12x.
| Step | Work |
|---|
| GCF first | 3x(x2โ4) |
| Diff. of squares | 3x(x+2)(xโ2) |
Always start with GCF โ it reveals hidden patterns.
Worked Example 2 โ Algebraic Identity on the SAT
If aโb=7 and a2โb2=35, find a+b.
| Step | Work |
|---|
| Recognize identity | a2โb2=(a+b)(aโb) |
| Substitute | 35=(a+b)(7) |
| Solve | a+b=5 |
Putting It All Together โ SAT Strategy
On the SAT, factoring isn't always labeled "factor this." It often appears disguised:
| SAT Question Type | Factoring Skill Needed |
|---|
| "Simplify the expression" | Factor and cancel |
| "How many solutions?" | Factor, count zeros |
| "What is the value of...?" | Factor to reveal identity |
| "Which is equivalent?" | Factor and match |
| "Find the zeros" | Factor and solve |
Worked Example 3 โ SAT-Style Identity Problem
If 9x2โ6x+1=0, what is the value of 3xโ1?
| Step | Work |
|---|
| Recognize | 9x2โ6x+1=(3xโ1) |
Answer: 3xโ1=0. No need to find x at all!
Worked Example 4 โ Disguised Difference of Squares
Compute 10032โ9972 without a calculator.
| Step | Work |
|---|
| Identity | a2โb2=(a+b)(a |
SAT Factoring Patterns Cheat Sheet
| Pattern | Formula | Example |
|---|
| Difference of squares | a2โb2=(a+b |
Name That Factoring Pattern ๐
Identify which factoring technique applies to each expression.
Key Takeaways โ Part 7
| Technique | When to Use | Key Move |
|---|
| GCF | Always first | Factor out common factor |
| Diff. of squares | a2โb2 | (a+b)(aโb) |
| Perfect square | a2ยฑ2ab+b2 | (aยฑ |
| Trinomial | ax2+bx+c | Find factors of ac that add to b |
| Grouping | 4 terms | Pair, factor, extract binomial |
| Disguised quad. | Even powers like x4,x6 | Let u=xn |
| Identities | "Find a+b" or "Find x2+1/x2" | Expand or factor known identity |
Full Topic Summary โ Polynomials & Factoring
| Part | Core Skill |
|---|
| 1 | Polynomial basics, adding/multiplying, special products |
| 2 | Factoring techniques: GCF, diff. of squares, trinomials |
| 3 | Polynomial division: long division, synthetic, remainder theorem |
| 4 | Zeros, multiplicity, end behavior, building from roots |
| 5 | Rational expressions: simplify, add, multiply, restrictions |
| 6 | Graphs, transformations, matching equation to graph |
| 7 | Review: decision tree, identities, SAT strategy |
2
2
+
ab+
b2)
4
โ
60
| Rewrite middle | 6x2+15xโ4xโ10 |
| Group | (6x2+15x)+(โ4xโ10) |
| Factor groups | 3x(2x+5)โ2(2x+5) |
| Extract common | (3xโ2)(2x+5) |
c>0
| (xโ?)(xโ?) |
| If c<0 | One positive, one negative | (x+?)(xโ?) |
โ
49=
(x+
7)(xโ
7)
2
+
10x+
25=
(x+
5)2
2
+
7x+
12=
(x+
3)(x+
4)
2
+
11xโ
10
3
x2
โ
3x
+
2+
x+13โ
c=1
| Coefficients 1,โ4,7 โ result 1,โ3 remainder 4 |
| Write result | xโ3+xโ14โ |
| Min. degree | 1+2+1=4 |
5u+
4=
(uโ
1)(uโ
4)
| Back-substitute | (x2โ1)(x2โ4)=(x+1)(xโ1)(x+2)(xโ2) |
| Count | 4 distinct x-intercepts |
2
โ
)
โฏ
2
โ
x
โ
2
x
โ
6
โ
=
(x+3)(xโ1)x2โ3xโ6โ
1
โ
x1โโ31โ
โ
3xโ
x1โ+3xโ
31โ
3xโ
x1โโ3xโ
31โ
โ
| Simplify | 3+x3โxโ |
factor
| x+5x+2โ | โ No | x is a term, not a factor |
| xx2+xโ | โ
Yes | Factor first: xx(x+1)โ=x+1 |
3
)
| (โ1)(โ2)(โ3)=โ6 |
| 2(xโ1)(xโ2)(xโ3) | 2(โ6)=โ12 | โ |
| โ(xโ1)(xโ2)(xโ3) | โ(โ6)=6 | โ |
f(x)โ3
2
| Set equal to 0 | (3xโ1)2=0 |
| Solve | 3xโ1=0 |
โ
b)
| Apply | (1003+997)(1003โ997)=(2000)(6) |
| Answer | 12,000 |
)
(
a
โ
b)
| x2โ9=(x+3)(xโ3) |
| Perfect square trinomial | a2ยฑ2ab+b2=(aยฑb)2 | x2+6x+9=(x+3)2 |
| Sum of cubes | a3+b3=(a+b)(a2โab+b2) | x3+8=(x+2)(x2โ2x |
| Difference of cubes | a3โb3=(aโb)(a2+ab+b2) | x3โ27=(xโ3)(x2+3x |
b
)2
+
4)
+
9)