What are Exponents? Exponents are used to show repeated multiplication of a number by itself. For example, 7 × 7 × 7 can be represented as 73. • the exponent is ‘3’ which stands for the number of times the number 7 is multiplied. • 7 is the base here which is the actual number that is getting multiplied. What are Exponents? So basically exponents or powers denotes the number of times a number can be multiplied. If the power is 2, that means the base number is multiplied two times with itself. Some of the examples are: 34 = 3×3×3×3 105 = 10×10×10×10×10 z3 = z × z × z a1 = a a2 = a x a a3 = a x a x a a4 = a x a x a x a . . . a7 = a x a x a x a x a x a x a … and so on ! Check your Understanding Assignment - Complete: • WKS #1 Introducing Exponents 1 • WKS #2 Expanded Form to Exponential Form Turn in completed worksheets in the box Lesson #2 Exponent Rules Rules of Exponents With Examples Suppose, a number ‘a’ is multiplied by itself n-times, then it is represented as an where a is the base and n is the exponent. Exponents follow certain rules that help in simplifying expressions which are also called its laws. There are different laws or rules defined for exponents. The important laws of exponents are shown at the right: Power of One An exponent tells you how many times the base number is used as a factor. ... Any number raised to the power of one equals the number itself, such as; a1 = a where ‘a’ is any non-zero term. Example: What is the value of 71 – 31 ? Solution: 71 – 31 = 7 – 3 = 4 Power of Zero According to this rule, when the power of any integer is zero, then its value is equal to 1, such as; a0 = 1 where ‘a’ is any non-zero term. Example: What is the value of 50 + 22 + 40 + 71 – 31 ? Solution: 50 + 22 + 40 + 71 – 31 = 1 + 4 + 1 + 7 – 3 = 10 Negative Exponent Rule According to this rule, if the exponent is negative, we can change the exponent into positive by writing the same value in the denominator and the numerator holds the value 1. Example: Find the value of 2-2 Solution: 2-2 can be written as 1/22 = 1/4 In other words, we can say that, if “a” is a non-zero number or non-zero rational number, we can say that a-m is the reciprocal of am. a0 = 1 Check your Understanding Assignment - Complete: • WKS #3 Introduction to Exponents 0 a = 1 1 a = a Turn in completed worksheets in the box Lesson #3 Exponent Rules a0 = 1 a1 = a a2 = a x a a3 = a x a x a a4 = a x a x a x a … and so on ! Check your Understanding Product With the Same Bases As per this law, for any non-zero term a, am × an = am+n where m and n are real numbers. Example: What is the simplification of 55 × 51 ? Solution: 55 × 51 = 55+1 = 56 Example: What is the simplification of (−6)-4 × (−6)-7? Solution: (−6)-4 × (−6)-7 = (-6)-4-7 = (-6)-11 Note: We can state that the law is applicable for negative terms also. Therefore the term m and n can be any integer. Use the Exponent Product Rule and answer in a single exponent. am × an = am+n Check your Understanding Use the Exponent Product Rule and answer in a single exponent. Quotient with Same Bases As per this rule, am / an = am-n where a is a non-zero term and m and n are integers. Example: Find the value when 10-5 is divided by 10-3. Solution: 10-5 / 10-3 = 10-5-(-)3 = 10-5+3 = 10-2 = 1 / 100 Use the Exponent Quotient Rule and answer in a single exponent. am / an = am-n Check your Understanding Use the Exponent Quotient Rule and answer in a single exponent. Assignment - Complete: • WKS # Turn in completed worksheets in the box Lesson #4 Exponent Rules Power Raised to a Power According to this law, if ‘a’ is the base, then the power raised to the power of base ‘a’ gives the product of the powers raised to the base ‘a’, such as; (am)n = amn where a is a non-zero term and m and n are integers. Example: Simplify and write the exponential (23)3 Solution: (23)3 = 23x3 = 29 (am)n = amn Check your Understanding Product to a Power As per this rule, for two or more different bases, if the power is same, then; an bn = ( ab )n where a is a non-zero term and n is the integer. Example 5: Simplify and write the exponential 2-3 x 5-3 Solution: 2-3 x 5-3 = (2 × 5)-3 = 10-3 an bn = ( ab )n 1) 52 • 32 2) 93 • 43 3) 37 • 87 4) a11 • b11 5) x5 • y5 6) 71 • 111 Check your Understanding 1) 44 • 9 4 2) 26 • 5 6 3) 122 • 32 4) 615 • v15 5) w5 • y5 6) r9 • 29 7) k0 • 110 8) x3 • y3 Assignment - Complete: • WKS # Turn in completed worksheets in the box Lesson #5 Exponent Rules Quotient to a Power As per this law, the fraction of two different bases with the same power is represented as; an / bn = (a / b)n where a and b are non-zero terms and n is an integer. Example: Simplify the expression and find the value: 153 / 53 Solution: 153 / 53 = ( 15 / 5 )3 = 33 = 27 n a / n b = (a / n b) Check your Understanding Fractional Exponent Rule The fractional exponent rule is used, if the exponent is in the fractional form. Here, a is called the base, and 1/n is the exponent, which is in the fractional form. Thus, a1/n is said to be the nth root of a. Example: Simplify: 41/2 Solution: According to the fractional exponent rule, 41/2 can be written as √4 41/2 = √4 = 2 (As, the square root of 4 is 2) Fractional Exponent Rule Check your Understanding Assignment - Complete: • WKS # Turn in completed worksheets in the box