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This comprehensive guide explores the intricacies of irrational numbers, mixed and entire radicals, as well as the properties of exponents. It defines rational and irrational numbers and provides clear examples to differentiate between them. The guide also covers simplification of radicals using prime factorization and how to express fractional exponents in both radical and exponential forms. Key rules and examples illustrate the relationships between reciprocals and the laws of exponents, making this an essential resource for mastering fundamental mathematical concepts.
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Roots and Powers Hughes, Cynthia, Cherie, Scarlett
1 Review Time 2 Irrational Number Mixed and Entire Radicals Fractional Exponents & Radicals 3 Negative Exponents, Reciprocals, and the Exponent Laws Root Power & 4
Part 1 Irrational Number By hughes
Classifying and Ordering Numbers IRRATIONAL NUMBERS
Rational numbers are numbers that can be written in the form of a fraction or ratio, or more specifically as a quotient of integers • Any number that cannot be written as a quotient of integers is called an irrationalnumber • ∏ is one example of an irrationalnumber…. • √0.24, 3√9, √2, √1/3, 4√12, e • Some examples of rationalnumbers? • √100, √0.25, 3√8, 0.5, 5/6, 7, 5√-32
Can you think of any more? Rational numbers: Irrationalnumbers:
Rational Vs. Irrational Numbers • You should have noticed that the decimal representation of a rational number either terminates, or repeats • 0.5, 1.25, 3.675 • 1.3333…., 2.14141414….. • The decimal representation of an irrational number neither terminates nor repeats • 3.14159265358………..
So…………………………………………………. • Which of these numbers are rational numbers and which are irrational numbers? • √1.44, √64/81, 3√-27, √4/5, √5 R R R I I
Exact Values Vs. Approximate Values • When an irrational number is written as a radical, for example; √2 or 3√-50, we say the radical is the exact valueof the irrational number. • When we use a calculator to find the decimal value, we say this is an approximate value • We can approximate the location of an irrational number on a number line
Example 1 Order these numbers on a number line from least to greatest: 3√13, √18, √9, 4√27, 3√-5 3√13 ≈ 2.3513… √18 ≈ 4.2426… √9 = 3 4√27 ≈ 2.2795… 3√-5 ≈ -1.7099… From least to greatest: 3√-5, 4√27, 3√13, √9, √18
Part 2 Mixed and Entire Radicals By Cherie
Example 1 Simplify the radical √80 Simplifying Radicals Using Prime Factorization • Solution: • √80 = √8*10 • = √2*2*2*5*2 • = √(2*2)*(2*2)*5 • = √4*√4*√5 • =2*2*√5 • =√5
Multiple Answers • Some numbers, such as 200, have more than one perfect square factor • The factors of 200 are: 1,2,4,5,8,10,20,25,40,50,100,200 • Since 4, 25, and 100are perfect squares, we can simplify √200 in three ways: • 2√50, 5√8, 10√2 • 10√2 is in simplest form because the radical contains no perfect square factors other than 1.
Example 2) Writing Radicals in Simplest Form • Write the radical in simplest form, if possible. • 3√40 • Solution: • Look for the perfect nth factors, where n is the index of the radical. • The factors of 40 are: 1,2,4,5,8,10,20,40 • The greatest perfect cube is 8 = 2*2*2, so write 40 as 8*5. • 3√40 = 3√8*5 = 3√8*3√5 = • 23√5 • Your turn: • Write the radical in simplest form, if possible. • √26, 4√32 • Cannot be simplified, 24√2
Mixed and Entire Radicals • Radicals of the form n√x such as √80, or 3√144 are entire radicals • Radicals of the form an√x such as 4√5, or 23√18 are mixed radicals • (mixed radical entire radical)
Example 3) Writing Mixed Radicals as Entire Radicals • Write the mixed radical as an entire radical • 33√2 • Solution: • Write 3 as: 3√3*3*3 = 3√27 • 33√2 = 3√27 * 3√2 = 3√27*2 = • 3√54 • Your turn: • Write each mixed radical as an entire radical. • 4√3, 25√2 • √48, 5√64
Review • Multiplication Property of Radicals is: • n√ab = n√a * n√b, where n is a natural number, and a and b are real numbers • to write a radical of index n in simplest form, we write the radicand as a product of 2 factors, one of which is the greatest perfect nth power • Radicals of the form n√x such as √80, or 3√144 are entire radicals • Radicals of the form an√x such as 4√5, or 23√18 are mixed radicals
Part 3 Fractional Exponents and Radicals By Cynthia
Powers with rational exponents with numerators 1 When n is a natural number and x is a rational number!!!!!!
Tryit Evaluate each power without using a calculator: 271/3 271/3 = 3√27 = 3 0.491/2 0.491/2 = √0.49 = 0.7
Powers with Rational Exponents When m and n are natural numbers, and x is a rational number: xm/n = (x1/n)m = (n√x)m And: xm/n = (xm)1/n = n√xm
TRY IT Write 402/3 in radical form in 2 ways ANSWER: Use am/n = (n√a)m or n√am 402/3 = (3√40)2 or 3√402
Review Powers with Rational Exponents with Numerator 1 When n is a natural number and x is a rational number: x1/n = n√x Powers with rational exponents When m and n are natural numbers, and x is a rational number: xm/n = (x1/n)m = (n√x)m And: xm/n = (xm)1/n = n√xm
Part 4 Negative Exponents, Reciprocals, and the Exponent Laws By Scarlett
Basic Reciprocals 4 x ¼ = 1 2/3 x 3/2 = 1 Any two numbers that have a product of 1 are calledreciprocals Also Applies to Powers am x an = am+n
Basic Laws of Exponents When x is any non-zero number and n is a rational number, x-n is the reciprocal of xn x-n = (1/x)n (1/x)-n = xn, x ≠ 0 Product of Powers: am x an = am+n Quotient of Powers: am/an = am-n, a ≠ 0 Power of a Power: (am)n = amn Power of a Product: (ab)m = ambm Power of a Quotient: (a/b)m = am/bm, b ≠ 0
Example Example 1 • Solution: • According to the Law: • x-n = (1/x)n • 3-2 = (1/3)2 • 1/9 Evaluate the power below: 3-2
Example Example 2 • Solution: • According to the Law: • (1/x)-n = xn, x ≠ 0 • (-3/4)-3 = (-4/3)3 • -64/27 Evaluate the power below: (-3/4) -3
Example • Solution: • 8-2/3 = (1/8)2/3 = 1/(3√8)2 • (1/2)2 • ¼ • x-n = (1/x)n • (1/x)-n = xn, x ≠ 0 Example 3 Evaluate the power below: 8-2/3
Example Example 4 • First use the quotient of powers law • 4/2 x a-2/a2 x b2/3/b1/3 = 2 x a(-2)-2 x b2/3-1/3 • 2a-4b1/3 • Then write with a positive exponent • 2b1/3/a4 Simplify the expression 4a-2b2/3/2a2b1/3
Your Turn Evaluate the power below: (Choose only 2 of them) 1) (9/16)-3/2 2) (7/24) -1/9 3) (9/20) 7/4 4) (25/10) -1/3
Thank Made by Math Group#6 Scarlett, Cherie, Cynthia and Hughes You