* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Transition to College Math Review Notes Name R.1 Algebra and
Big O notation wikipedia , lookup
Location arithmetic wikipedia , lookup
Georg Cantor's first set theory article wikipedia , lookup
Infinitesimal wikipedia , lookup
Collatz conjecture wikipedia , lookup
Mathematics of radio engineering wikipedia , lookup
Large numbers wikipedia , lookup
Hyperreal number wikipedia , lookup
Positional notation wikipedia , lookup
Vincent's theorem wikipedia , lookup
Proofs of Fermat's little theorem wikipedia , lookup
System of polynomial equations wikipedia , lookup
Real number wikipedia , lookup
Transition to College Math Review Notes Name ___________________________________________________________________ R.1 Algebra and Real Numbers Essential Question(s): How do you graph real numbers on a number line and add, subtract, multiply, and divide real numbers? Definitions: Set A collection of objects. Note: Two sets are equal if they have exactly the same objects) Element (member) Each object in a set Finite Elements can be counted Infinite Elements can be counted without end Empty (null) Set Set that contains no elements { }. Note: the empty set is a subset of any set. Listing (roster) Method Lists the elements of a set. Ex: A = { 1, 2, 3, 4 } Set Builder (rule) notation Uses a rule to describe the members of the set. Ex: {x | x > 5} (Read “x such that x is greater than 5”) Variable A symbol used as a placeholder for the elements of a set with two or more elements Replacement Set The elements of a set represented by a variable Constant A symbol that names exactly one object Subset Element(s) that are members of a set means… “is an element of…” Page 1 Transition to College Math means… Review Notes “is a subset of…” Equal Sets Two or more sets having exactly the same elements Intersection of Sets A B The set of elements common to both sets A and B Union of Sets A B The set of elements that are members of set A or of set B or of both sets natural numbers {1, 2,3,...} whole numbers {0,1, 2,3,...} integers {..., 3, 2, 1, 0,1, 2,3,...} the whole numbers and their opposites rational numbers irrational numbers real numbers numbers than can be written as a quotient of two integers → rational means fractional (decimals terminate or repeat) 5 7 3 9 Ex. , , 0.5, 4 1 numbers that are not rational (nonrepeating and nonterminating decimal numbers) Ex. 7, , 13 rational numbers and irrational numbers Examples: 1. List all possible subsets of A = {1, 2, 3} {1, 2, 3} {1, 2} {1, 3} {2, 3} {1} {2} {3} 0 2. Determine if the following are true or false a. 2 {1, 2,3} F d. 0 {x, y, z} F b. { y, x, z} {x, y, z} T e. {w, x, y, z} {x, y, z} F c. { y, x, z} {x, y, z} T Page 2 Transition to College Math Review Notes 3. Write the following sets using set builder notation a. {2, 4, 6, 8, 10} {x | x an even integer between 2 and 10 inclusive} b. {1, 2, 3, 4, 5} {x | x an integer between 1 and 5 inclusive} 4. Write the following set using the listing method: {x | x is a letter in the word ALGEBRA} 5. Given set B 2, 1 , 3 2, 0, 8 , , 3 a. Rational numbers {A, L, G, E, B, R} 36 , list the following 1 8 2, , 0, , 3 3 b. Irrational numbers 2, 36 2, 0, 36 0, 36 36 c. Integers d. Whole numbers e. Natural numbers 6. Find the intersection: {1, 2, 3, 4, 5, 6} {2, 4, 6, 8} 7. Find the union: {1, 2, 3, 4, 5, 6} {2, 4, 6, 8} {2, 4, 6} {1, 2, 3, 4, 5, 6, 8} Define or describe the following: Graph of a number The point on a number line that is paired with the number Coordinate of a point The number paired with a point on a number line Origin The zero point on a number line Page 3 Transition to College Math Review Notes Real Number Any number that is positive, negative or zero. Positive Real Number A number paired with a point on the positive side of a number line Negative Real Number A number paired with a point on the negative side of a number line > means … greater than Inequality Symbols: Examples. < means … less than 4 1. Graph the numbers 1.5, , 2, 4 , 3, and 2.75 on a number line. Then list them in 3 increasing order. -4 -3 -2 -1 0 1 2 3 4 4, 2.75, , 1.5, 2, 3 3 2. State two inequalities, one with > and one with <, for the coordinates of the points shown below. -3 -2 -1 0 1 2 3 2 1 OR 1 2 Properties of Equality Statement For all real numbers a, b, and c. Reflexive Property aa If a b, then b a. Symmetric Property If a b and b c, then a c. Transitive Property If a b, then a c b c and c a c b. Addition Property Multiplication Property If a b, then ac bc and ca cb. Field Properties of Real Numbers For all real numbers a, b, and c. Closure Properties: a + b and ab are unique real numbers Examples Let a = 12, b = 6, and c = 5. 12 6 18 12(6) 72 Page 4 Transition to College Math Review Notes 12 6 6 12 Commutative Properties: a+b=b+a ab = ba Associative Properties: (a + b) + c = a + (b + c) (ab)c=a(bc) Identity Properties: There are unique real numbers 0 and 1 such that: of Addition: a + 0 = a and 0 + a = a of Multiplication: a 1 a and 1 a a Inverse Properties: Property of Opposites: For each a, there is a unique real number –a such that: a + (-a) = 0 and (-a) + a = 0 12(6) 6(12) (12 6) 5 12 (6 5) (12 6)5 12(6 5) 12 0 12 0 12 12 12(1) 12 1(12) 12 12 (12) 0 12 12 0 Property of Reciprocals: For each a except 0, there is a unique real number 1 a 12 such that: 1 1 a 1 and a 1 a a Distributive Property: a(b c) ab ac (b c)a ba ca 1 1 12 1 12 1 12 12(6 5) 12(6) 12(5) (6 5)12 6(12) 5(12) Zero Properties a 0 0 a 0 Any number multiplied by zero is zero ab = 0 iff a = 0 or b = 0 The product ab can only equal zero if a or b or both equal zero. Properties of Fractions Note: Denom 0 Properties of Negatives Note: b 0 – (– a) = a (– a)b = – ab (– a)( – b) = ab – 1(a) = – a a c b d ka a kb b a c a b d b a a a b b Examples: b a a a a b b b b a c ac b b b Page 5 d c iff ad = bc a c ac b d bd a c ac b b b a c ad cb b d bd Transition to College Math Review Notes Examples: 1. Is the set of odd numbers closed under addition? Use an example to justify your response. Odd + Odd = Odd? 7 + 3 = 10 NO 2. Is the set of odd numbers closed under multiplication? Use an example to justify your response. (Odd) (Odd) = Odd (7) (3) = 21 YES 3. Is the set of integers closed under subtraction? Use an example to justify your response. Integer – Integer = Integer? –5–3=–8 YES 4. Is the set of whole numbers closed under subtraction? Use and example to justify your response. Whole number – Whole number = Whole number? 6–9=–3 NO 5. Justify each step using a property in this section 1. 2. (7 3) [(7) (3)] [(7 3) (7)] (3) [7 (7) 3] (3) 3. [0 3] (3) 4. 3 (3) 5. 0 Page 6 Associative Property Of Addition Associative and Commutative Properties Inverse Property of Addition (Property of Opposites) Identity Property of Addition Inverse Property of Addition (Property of Opposites) Transition to College Math Review Notes R.2 Exponents Essential Question(s): How do you simplify exponents and express numbers using scientific notation? Integer Exponents 1. For n a positive integer: a n a a .... a n factors of a 2. For n = 0: a0 1 a0 0 0 is not defined 3. For n a negative integer: 1 an n a Examples: 1. 6360 1 2. ( x 2 )0 x0 1 3. 105 1 1 0.00001 5 10 10000 4. 1 103 1000 103 5. 1 x4 x 4 u 7 v3 6. 3 7 v u Page 7 Transition to College Math Review Notes Properties of Integer Exponents m 1. a a a m 2. a n n m mn a mn am a 4. m b b b0 a mn am 5. n 1 a nm a a0 3. (ab)m a mbm Examples: 1. (5 x 3 )(3x 4 ) 15 x 9 y 7 3 2. 3 4 6y 2y 3. 2 x 4 (2 x)4 2 x 4 16 x 4 14 x 4 4. (3x 4 y 3 )2 32 x 8 y 6 y6 9 x8 3 x2 y12 5. 4 6 x y 6m2 n3 2n 5 6. 15m1n2 5m 3 x 3 7. 4 4 x 9 y y 8. 1 ( a b) 2 2 ( a b) Page 8 Transition to College Math Review Notes Definition of an nth Root a is an nth root of b if Example: 2 is a 4th root of 16 since an b 2 4 16 Number of Real nth Roots of a Real Number b n Even n Odd b Positive 2 Example: 2 are 4th roots of 16 1 Example: 3 is the cube root of 27 b Negative 0 Example: – 4 has not real square roots 1 Example: – 3 is the only real root of – 27 1 n b , Principal nth Root 1 For n a natural number and b a real number, b n is the principal nth root of b, defined as follows: 1 1. If n is even and b is positive, b n then represents the positive nth root of b. 1 2. If n is even and b is negative, then b n does not represent a real number. 1 3. If n is odd, then b n represents the real nth root of b. 1 4. 0 n 0 Page 9 Transition to College Math Review Notes Anatomy of a Rational Exponent 5 Base 2 3 Exponent Index Examples: 1 1. 4 2 4 2 1 2 2. 4 4 2 1 3. (4) 2 4 not real 1 3 4. 8 3 8 2 1 3 5. (8) 3 8 2 1 8 6. 0 8 0 0 3 2 7. 9 93 9 9 9(3) 27 4 3 8. (27) 3 (27)4 27 3 27 27(3) 81 9 4 13 3 1 9. 5 y 4 2 y 3 10 y 12 12 10 y 12 1012 y13 10 y12 y 4 3 1 16 y 10. 2 x 4 y 4 16 x 3 y 3 x 12 8x 11. 2 x3 3 translates to 1 1 3 6 8 1 6 2 x 2 36 36 18 2 x 2 x 1 2 18 x x9 Page 10 52 Transition to College Math Review Notes Scientific Notation a 10n 1 a 10, n an integer, a in decimal form To convert from scientific notation to decimal form: 5.76 106 5.76 106 Exponent negative Decimal moved to the left Exponent positive Decimal moved to the right 0.00000576 5, 760, 000 To convert from decimal form to scientific notation: 0.00000576 5, 760, 000 Original number < 1 Power is negative Original number > 10 Power is positive 5.76 106 5.76 106 Examples: Write each number in scientific notation: 1. 430 4.3 102 2. 23,000 2.3 104 3. 345,000,000 3.45 108 4. 0.3 5. 0.0031 3.1103 6. 0.000000683 6.83 107 Write in standard decimal form: 1. 4 103 4,000 2. 5.3 105 530,000 3. 2.53 102 0.0253 4. 7.42 106 0.00000742 3 101 Page 11 Transition to College Math Review Notes R.3 Radicals Essential Question(s): What are the properties of radicals? How do you simplify radicals and convert to rational exponents? Anatomy of a Radical When in Simplified Form: 1. powers of factors in radicand are less than index 2. power of radicand and index cannot have common factor other than 1. 3. No radicals in denominator 4. No fractions within radical Exponents Index 5 32x 23 y 6 Radicand Define or describe the following: n Principle nth root of a real number n a b means b a If the index is even, than a and b are nonnegative. If the index is odd, a and b can be any real numbers. If n is odd, th n roots of perfect nth powers If n is even, n Product rule for nth roots th n Quotient rule for n roots n an a n an a ab n a n b a na , b0 b nb Properties of Radicals 1. n x x n 2. n xy x y n Page 12 n 3. n x y n n x y Transition to College Math Review Notes Examples: Change from rational exponent form to radical form. 1 1. u 5 5 u 2 2. (6 x 2 y 5 ) 9 9 (6 x 2 y 5 ) 2 9 36 x 4 y10 3. (3xy) 3 5 1 5 (3xy) 3 27 x3 y 3 Change from radical form to rational exponent form. 5 4. 4 9u (9u ) 1 4 4 5. 7 (2 x)4 (2 x) 7 1 6. 3 x3 y 3 ( x3 y 3 ) 3 Simplify. 7. 7 6 2 12 4 3 2 3 8. 9. (u 2 v 2 )7 u 2 v 2 3 x2 3 x2 8 2 18 x5 y 2 z 3 3x 2 | yz | 2 xz 10. 2 11. 4 1 27a3b3 4 3a5b3 4 81a8b6 3a 2b 4 b2 3a 2b(b 4 ) 3a 2b(b 2 ) 3a 2 | b | b Page 13 Transition to College Math 12. 9 1 9 2 3 1 3 Review Notes 1 3 9 2 3 1 3 1 3 2 3 1 3 8 x y 8 x y (2 ) x y 2 x y 3 2 x 2 y 6 1 3 2 1 3 11 1 1 1 4 4 4 4 3 2 4 6 (22 ) 6 2 3 3 2 3 13. 3 14. 6 2 2 2 8 2 15. 3 5 2 x 2 y 3 8 5 2 x 2 y 3 5 5 2 x 2 y 3 16. 5 3 mn2 3 mn 2 3 mn2 7 mn 3 3 mn2 4 mn 17. 3 6 4 18 4 3 3 2 4 3 18. 32 19. y 2 20. 3 3 4 9 4 3 2 3 8 3 2 3 8 5 2 3 y 4 x2 3 y 2 3 y2 4 y 2 y 8 y 2 y 8 x 3 y 3 x3 3 x 2 y 3 xy 2 3 y 3 x 3 x 2 y 3 xy 2 y Page 14 Transition to College Math Review Notes Eliminating a radical from a denominator is referred to as rationalizing the denominator. Examples: 6 6 2x 6 2x 3 2x 2x x 2x 2x 2x 1. x2 y3 2. 3. 4. 10 x3 10 x3 3 2 x 2 10 x3 3 2 x 2 5x2 3 2 x2 3 3 2 3 2 2 x 4x 2 x 2x 3 8c 9d 5 5. x 2 x 2 2 x 3 2 x2 3 x 4 x 6 2 x x 6 4x 9 2 x 3 2 x 3 2 x 3 4 x2 9 6. 3 5 3 5 7. (Hint: Remember Difference of Cubes a3 b3 (a b)(a 2 ab b2 ) ). 1 3 y 3 y2 1 3 y 3 y2 1 3 y 3 y2 1 1 1 y 1 3 y 1 3 y 1 3 y 3 y 2 1 3 y 3 y 2 3 y 3 y 2 3 y3 Page 15 Transition to College Math Review Notes R.4 Polynomials: Basic Operations Essential Question(s): How do you add, subtract, and multiply polynomials? Definitions: Polynomial An algebraic expression involving only the operations of addition, subtractions, multiplication, and raising to natural number powers Term Part of a polynomial separated by symbols Degree The highest exponent Degree of the Term The sum of the powers of the variables Degree of a Polynomial The degree of the nonzero term with the highest degree in the polynomial Coefficient The number in front of a variable Leading Coefficient The first number in an expression Constant Term The “Lone number” – without a variable Descending Order Highest to lowest Like Terms Polynomials that have exactly the same variable factors raised to the same powers Special Types Monomial – one term Example: 8x 2 y Binomial – two terms Example: 4 x 5 Trinomial – three terms Example: a 2 2ab b 2 Page 16 Transition to College Math Review Notes Examples: 1. Which of the following are polynomials? 3x 2 2 x 1 x 3 x 2 2 xy y 2 x 1 x2 2 2. Given the polynomial 3x5 6 x3 5 , what is the degree of the first term? The second term? The whole polynomial? 5 ; 3; 5 3. Given the polynomial 6 x 4 y 2 3xy 3 , what is the degree of the first term? The second term? The whole polynomial? 6; 4; 6 Remove parentheses and combine like terms. 4. 3(u 2 2v 2 ) (u 2 5v 2 ) 3u 2 6v 2 u 2 5v 2 4u 2 v 2 5. (m3 3m2 m 1) (2m3 m 3) m3 3m2 m 1 2m3 m 3 m3 3m2 2m 4 6. ( x3 2) [2 x3 (3x 4)] x 3 2 [2 x 3 3 x 4] x3 2 2 x3 3x 4 x3 3x 2 7. Add 3x 4 2 x3 4 x 2 , x 3 2 x 2 5 x , and x 2 7 x 2 . 3x 4 2 x3 4 x 2 x3 2 x 2 5 x x 2 7 x 2 3x 4 x3 5 x 2 2 x 2 8. Subtract 2 x 2 5 x 4 from 5 x 2 6 . 5 x 2 6 (2 x 2 5 x 4) 5x2 6 2 x2 5x 4 3x 2 5 x 10 Page 17 Transition to College Math Review Notes Multiplying Polynomials Monomial x Polynomial: Distribute 2(2 x 2 4 x 9) 4 x 2 8 x 18 Binomial x Binomial: First Outer Inner Last (2 x 3 y )(5 x 2 y ) 10 x 2 4 xy 15 xy 6 y 2 10 x 2 11xy 6 y 2 Polynomial x Polynomial: Clamshell Method (2 x 3)(3 x 2 2 x 3) 6 x3 4 x 2 6 x 9 x 2 6 x 9 6 x3 13 x 2 12 x 9 Special Products: a 2 b 2 (a b)(a b) 25 x 2 81 (5 x 9)(5 x 9) a 2 2ab b 2 (a b) 2 4 x 2 12 x 9 (2 x 3) 2 a 2 2ab b 2 (a b) 2 49 y 2 28 y 4 (7 y 2) 2 Examples: Multiply. 1. (2 x 3)(2x 2 3x 2) 4 x3 6 x 2 4 x 6 x 2 9 x 6 4 x3 13x 6 2. (4u 3v)(2u v) 8u 2 4uv 6uv 3v 2 8u 2 2uv 3v 2 3. (2 xy 3)(2 xy 3) Page 18 Transition to College Math Review Notes 4 x2 y 2 9 4. (m 4n)(m 4n) m2 16n 2 5. (2u 3v)2 4u 2 12uv 9v 2 6. (6 x y)2 36 x 2 12 xy y 2 Perform the indicated operations and simplify. 7. 2t {7 2[t t (4 t )]} 2t {7 2[t 4t t 2 ]} 2t {7 2[3t t 2 ]} 2t {7 6t 2t 2 } 2t 7 6t 2t 2 2t 2 4t 7 8. (u 3v)2 (2u v)(2u v) u 2 6uv 9v 2 (4u 2 v 2 ) u 2 6uv 9v 2 4u 2 v 2 3u 2 6uv 10v 2 9. (4 x y )3 (4 x y )(16 x 2 8 xy y 2 ) 64 x 3 32 x 2 y 4 xy 2 16 x 2 y 8 xy 2 y 3 64 x 3 48 x 2 y 12 xy 2 y 3 11. A plastic water pipe is 200 inches long, 2 inches thick, and has an outer radius of x inches. Write an algebraic expression in terms of x that represents the volume of the plastic used to construct the pipe. Simplify the expression. V x 2 (200) ( x 2) 2 (200) V 200 x 2 200 ( x 2 4 x 4) V 200 x 2 200 x 2 800 x 800 V 800 x 800 R.5 Polynomials: Factoring Page 19 Transition to College Math Review Notes Essential Question(s): How do you factor polynomials? Definitions: Prime Number An integer greater than one having no integral factors other than itself and one. Composite Number An integer greater than one that is not prime Methods to Factor Polynomials 1. GCF: ALWAYS FACTOR GCF FIRST! a. Find the GCF of each term b. Divide each term by the GCF. Ex. 3x3 15x2 3x2 ( x 5) 2. Difference of Square: a 2 b2 (a b)(a b) Two Terms Ex. 4 x 2 9 (2 x 3)(2 x 3) 3. Sum & Difference of Cubes: a3 b3 (a b)(a 2 ab b 2 ) a3 b3 (a b)(a 2 ab b 2 ) Ex. 8x3 y3 (2 x y)(4 x 2 2 xy y 2 ) 4. Perfect Square Trinomial: a 2 2ab b2 (a b)2 a 2 2ab b2 (a b)2 Ex. n2 4n 4 (n 2)2 Three Terms 5. AC Method to Factor Quadratic Polynomial ax 2 bx c : a. Multiply ac. b. Find factors of product of ac that has a sum equal to b. c. Rewrite bx term as the sum of factors found from Step 2. d. Factor by grouping. Ex. 2 x2 5x 3 2(3) 6 1, 6 1, 6 2, 3 2,3 1, 6 product is 6 and sum is 5 Page 20 2 x 2 1x 6 x 3 x(2 x 1) 3(2 x 1) (2 x 1)( x 3) Transition to College Math Four Terms Review Notes 6. Grouping: a. Rearrange terms into 2 subgroups and factor. Ex. x2 4x 4 4 y 2 xy 3 y 2 x 6 ( x 2 4 x 4) 4 y 2 y ( x 3) 2( x 3) ( x 2) 2 4 y 2 Factor as difference of squares. ( x 3)( y 2) ( x 2 2 y )( x 2 2 y ) Examples: Factor completely. 1. 3x3 y 6 x2 y 2 3xy3 3xy( x2 2 xy y 2 ) 2. 3 y (2 y 5) 2(2 y 5) (2 y 5)(3 y 2) 3. 4(2 x 5)(3x 1)2 6(2 x 5)2 (3x 1) 2(2 x 5)(3 x 1)[2(3x 1) 3(2 x 5)] 2(2 x 5)(3 x 1)[6 x 2 6 x 15] 2(2 x 5)(3 x 1)(12 x 17) 4. 2 x 2 6 x 5 x 15 2 x( x 3) 5( x 3) ( x 3)(2 x 5) 5. 2 pr ps 6qr 3qs 2 p(r s ) 3r (r s ) (r s )(2 p 3r ) 6. 2 x 2 7 xy 4 y 2 2 x 2 8 xy xy 4 y 2 2 x( x 4 y ) y ( x 4 y ) ( x 4 y )(2 x y ) 7. 4 x 2 15xy 4 y 2 4 x 2 16 xy xy 4 y 2 4 x( x 4 y ) y ( x 4 y ) ( x 4 y )(4 x y ) Page 21 Transition to College Math Review Notes 8. 4m2 12mn 9n 2 (2m 3n)2 9. x 2 16 y 2 ( x 4 y )( x 4 y ) 10. z 3 1 ( z 1)( z 2 z 1) 11. m 3 n3 (m n)(m2 mn n2 ) 12. 3x3 48 x 3x( x 2 16) 3x( x 4)( x 4) 13. x 2 y 2 4 y 4 x 2 ( y 2 4 y 4) x 2 ( y 2) 2 [ x ( y 2)][ x ( y 2)] ( x y 2)( x y 2) 14. 3u 4 3u 3v 9u 2 v 2 3u 2 (u 2 uv 3v 2 ) 15. 3m4 24mn3 3m(m3 8n3 ) 3m(m 2n)(m2 2mn 4n 2 ) 16. 3 x 4 5 x 2 2 3x 4 3x 2 2 x 2 2 3 x 2 ( x 2 1) 2( x 2 1) ( x 2 1)(3 x 2 2) ( x 1)( x 1)(3 x 2 2) Page 22 Transition to College Math Review Notes R.6 Rational Expressions Essential Question(s): How do you simplify and add, subtract, multiply, and divide rational expressions? How do you simplify complex fractions? Remember, Rational means… fractional Rational expression – the quotient of two polynomials Note: An Expression is a collection of terms or an incomplete mathematical thought while an equation is a completed thought having an answer. Note: Expressions can only be simplified while equations can be solved. I. The Domain of a Rational Expression The domain of an algebraic expression is… all real numbers except those that make the denominator equal to zero Example: Find the domain. 43 x 9 2 Look at the denominator. What values make x 2 9 0 ? ( x 3)( x 3) 0 x 3 OR x2 9 x 3 So, the domain is all real numbers except 3 or {x | x 3} II. Simplifying, Multiplying, and Dividing an Expression Simplify. Give restrictions Example: Simplify. 7 y 2 11y 6 y3 y 2 6 y Example: (7 y 3) ( y 2) y ( y 2) ( y 3) 7y 3 , y 0, 2, 3 y ( y 3) x2 x y 2 2y y 3x 1 x2 2y 3y x2 3y 2y 1 3x 2 2 Page 23 Transition to College Math III. Review Notes Adding and Subtracting Rational Expressions Use LCD Example: Find LCD: ( w 1)( w 1) w2 1 w 1 w2 1 w 1 w2 1 w 1 w 1 w2 1 w 1 w 1 w2 1 w2 2 w 1 w2 1 w2 1 2 w2 2 w 2 ( w 1)( w 1) 2( w2 w 1) ( w 1)( w 1) Example: 5 12 w 1 1 w 5 12 w 1 w 1 7 w 1 IV. Complex Rational Expressions Procedures: 1. Find the LCD for all denominators in the complex rational expression 2. Multiply by a form of “1” multiply the expression by 3. The result should be a simple rational expression. Page 24 LCD . LCD Transition to College Math Example: Find LCD: Review Notes m mn n n n m m m n n n m mn m m n mn n m2n m2 mn 2 n 2 m 2 (n 1) 2 n (m 1) m m m n mn n mn n m m2n m2 mn 2 n 2 m 2 (n 1) 2 n (m 1) OR 5 w1 Example: 12 w1 1 5 w w 1 w 12 w 5w 1 12 w 1 OR Page 25 1 5 w 1 12 w 5w 1 w w 12 w 1 5w 1 12 w 1