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nth Roots and Rational Exponents. Lesson 7.1 Goal: Evaluate nth roots of real numbers. Warm-up. 1. If an object travels at five feet per second, how many feet does it travel in one hour? 30 B. 300 C. 720 D. 1800 E. 18000
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nth Roots and Rational Exponents Lesson 7.1 Goal: Evaluate nth roots of real numbers
Warm-up 1. If an object travels at five feet per second, how many feet does it travel in one hour? 30 B. 300 C. 720 D. 1800 E. 18000 2. In a class of 78 students 41 are taking French, 22 are taking German and 9 students are taking both French and German. How many students are not enrolled in either course? A. 6 B. 15 C. 24 D. 33 E. 54 3. What is the average (arithmetic mean) of all the multiples of ten from 10 to 190 inclusive? A. 90 B. 95 C. 100 D. 105 E. 110
nth Roots b is the square root of a if b is the cube root of a if b is the fourth root of a if b is the nth root of a if The nth root of a can be written as where a is a real number and n is the index of the radical. refers to the positive nth root of a. refers to the negative nth root of a.
Number of Real nth Roots Let n be an integer greater than 1, and let a be a real number. If n is odd and a is any real number, then n has 1 real root! n a Examples
Number of Real nth Roots Let n be an integer greater than 1, and let a be a real number. If n is even and a is any positive real number, then n has 2 real roots! Examples
Number of Real nth Roots Let n be an integer greater than 1, and let a be a real number. If n is even and a is zero, then n has 1 real root! Examples
Number of Real nth Roots Let n be an integer greater than 1, and let a be a real number. If n is even and a is any negative real number, then n has NO real root! Examples
Number of Real nth Roots Number of Real nth Roots Let n be an integer greater than 1, and let a be a real number.
Rational Exponents: You do not have to use a radical to write an nth root of a. You can write an nth root of a using a fraction as an exponent. The denominator of each rational exponent is equal to the index of the radical.
Example 2: Evaluate. Does not exist.
Rational Exponents: Rational Exponents You can also use a fraction as an exponent to write a combination of a power and an nth root.
Assignment Worksheet 7.1