Do Now Exponent Rules pre-assessment
Agenda Handouts Package for part zero.
Exponent Rules Or Laws of Exponents
Base x Exponent Remember! 4
In an expression of the form an, a is the base, n is the exponent, and the quantity an is called a power. The exponent indicates the number of times that the base is used as a factor.
24 is read “2 to the fourth power.” Reading Math
Zero Rules Example:
Is undefined
One Rules Example:
More Rules
The following suggests a rule for multiplying powers with the same base. 24 • 22 = (2 • 2 • 2 • 2) • (2 • 2) = 26 a3 • a2 = (a • a • a) • (a • a) = a5 Notice that the sum of the exponents in each expression equals the exponent in the answer: 4 + 2 = 6 and 3 + 2 = 5.
A. 42 • 44 4 Add exponents. 4 B. x2 • x3 x Add exponents. x Check It Out! Example 1 Simplify each expression. Write your answer in exponential form. A. 42 • 44 4 2 + 4 Add exponents. 4 6 B. x2 • x3 x 2 + 3 Add exponents. x 5
Additional Example 1: Multiplying Powers with the Same Base Simplify each expression. Write your answer in exponential form. A. 66 • 63 6 6 + 3 Add exponents. 6 9 B. n5 • n7 n 5 + 7 Add exponents. n 12
Example 2A: Simplifying Expressions with Negative Exponents Simplify the expression. 3–2 The reciprocal of .
The following suggests a rule for dividing powers with the same base. 3 6 32 = = 3 • 3 • 3 • 3 = 34 3 3 3 3 3 3 3 3 1 x 5 x3 = = x • x = x2 x x x x x x x x 1 Notice that the difference between the exponents in each expression equals the exponent in the answer: 6 – 2 = 4 and 5 – 3 = 2.
Additional Example 2: Dividing Powers with the Same Base Simplify each expression. Write your answer in exponential form. 7 5 3 A. 7 5 – 3 Subtract exponents. 7 2 x 10 9 B. x 10 – 9 Subtract exponents. x Think: x = x 1
A. B. 9 9 9 Subtract exponents. 97 e e e Subtract exponents. e Check It Out! Example 2 Simplify each expression. Write your answer in exponential form. 9 9 A. 9 2 9 9 – 2 Subtract exponents. 97 e 10 B. e 5 e 10 – 5 Subtract exponents. e 5
RAISING A POWER TO A POWER To see what happens when you raise a power to a power, use the order of operations. RAISING A POWER TO A POWER Show the power inside the parentheses. (c3)2 = (c ● c ● c)2 Show the power outside the parentheses. = (c ● c ● c) ● (c ● c ● c) = c6 Simplify.
RAISING A POWER TO A POWER Reading Math (94)5 is read as “nine to the fourth power, to the fifth power.”
Additional Example 3: Raising a Power to a Power Simplify each expression. Write your answer in exponential form. A. (54)2 (54)2 54 • 2 Multiply exponents. 58 B. (67)9 (67)9 67 • 9 Multiply exponents. 663
A. (33)4 (33)4 33 • 4 Multiply exponents. 312 B. (48)2 (48)2 48 • 2 Check It Out! Example 3 Simplify each expression. Write your answer in exponential form. A. (33)4 (33)4 33 • 4 Multiply exponents. 312 B. (48)2 (48)2 48 • 2 Multiply exponents. 416
Exponential Properties Practice Work on Handout Exponential Properties Practice