EXPONENTS
If ‘A’ is any number and m is the natural number and if we wish to multiply unlimited or m times of A each other, then we can write or express like that-
( A x A x A x A x …………… m times taken ) = Aᵐ, where ‘m’ is the exponents and ‘A’ is the base.
There are some rules of ‘EXPONENTS’ are described below which we have to follow every time in application-
1) If ‘A’ is any number and let x & y are the natural numbers, then-
Aˣ x Aʸ = A⁽ˣ⁺ʸ⁾
2) If ‘A’ is any number, m & n are the natural number, where m > n then-
Aᵐ
--------- = A ⁽ ᵐˉⁿ ⁾
Aⁿ
3) If ‘A’ is any number, m & n are the natural number, then
( Aᵐ) ⁿ = Aᵐⁿ
4) If ‘A’ & ‘B’ are any number and m is a natural number, then
Aᵐ x Bᵐ = (AB)ᵐ
5) If ‘A’ & ‘B’ are any number and m & n are natural numbers, then
Aᵐ x Bⁿ = Aᵐ Bⁿ
6) If ‘A’ is any number and m is a natural number, then
(-A)ᵐ = Aᵐ when ‘m’ is even.
And (-A)ᵐ = - Aᵐ when ‘m’ is odd.
7) If ‘A’ is any number, then
A⁰ = 1
A¹ = A
Example.1) Please write the value of 7⁴
Ans.) 7⁴ = 7 x 7 x 7 x 7 = 2401
Step.1) First observed in given numbers how much power or natural number is given.
Step.2) Multiply normally the given number 7 as much as time as per given Power or natural numbers (i.e. 4) is provided. Here number 7 is to be multiplied by 4 times and the result is 2401.
Step.3) Value comes with negative (-) sign or value because as per rules-
Aᵐ = Aᵐ or (+) Aᵐ when ‘m’ is even. So, 2401
or (+) 2401 is the actual/final result. (Ans.)
Example.2) Please write the value of (-2)⁷
Ans.) (-2)⁷ = (-2) x (-2) x (-2) x (-2) x (-2) x (-2) x (-2) = -128
Step.1) First observed in given numbers how much power or natural number is given.
Step.2) Multiply normally the given number 2 as much as time as per given Power or natural numbers (i.e. 7) is provided. Here number 2 is to be multiplied by 7 times and the result is 128.
Step.3) Value comes with negative (-) sign or value because -
as pr rules (-A)ᵐ = - Aᵐ when ‘m’ is odd. 7 is odd number
So, -128 is the actual/final result. (Ans.)
Example.3) Please write the value of (-3)⁸
Ans.) (-3)⁸ = (-3) x (-3) x (-3) x (-3) x (-3) x (-3) x (-3) x (-3) = 6561
Step.1) First observe in given numbers how m power or natural number is given.
Step.2) Multiply normally the given number 3 as much as time as per given Power or natural numbers (i.e. 8) is provided. Here number 3 is to be multiplied by 8 times and the result is 6561.
Step.3) Value comes with negative (-) sign or value because -
as pr rules (-A)ᵐ = Aᵐ when ‘m’ is even.
So , 6561 is the actual/final result. (Ans.)
4) Write 625 as a power of 5.
Step.1) First find the prime factorization of the given number.
Step.2) After completing prime factorization of the given number observe how many base has come with their exponents. Clearly shown that only 5 has come 4 times .
Step.3) Clearly shown that 5 has come 4 times, so 5 is the base and 4 its exponents.
So, it can be written as 5⁴.
625 = 5 x 5 x 5 x 5 = 5⁴. (Ans.)
5) Write 38880 in exponential form.
Step.1) First find the prime factorization of the given numbers.
Step.2) After completing prime Factorization of the given number observe how many base and their exponents we can find.
Step.3) Clearly shown that 2 has come 5 times, 5 has come 1 time and 3 has come 5 times. so it can be written as 5⁴.
Step.4) 2 has come 5 times, so 2 is base 5 its exponent. It can be written 2⁵. 5 has come 1 time, so 5 is base and 1 its exponent. It can be written 5¹. 3 has come 5 times, so 3 is base and 5 its exponent. It can be written 3⁵.
Step.5.) Exponential form can be written as multiplication of base with their exponents like
2⁵ x 5¹ x 3⁵
38880 = 2 x 2 x 2 x 2 x 2 x 5 x 3 x 3 x 3 x 3 x 3
= (2 x 2 x 2 x 2 x 2) x 5 x (3 x 3 x 3 x 3 x 3)
= 2⁵ x 5¹ x 3⁵ (Ans.)
6) Write the product of number 3ᶟ and 3⁵ as single power.
Ans.) 3ᶟ and 3⁵
= 3ᶟ x 3⁵ = 3 ᶟ⁺⁵ = 3⁸
Step.1) Observe the given two-digit, where the base are the same but exponents are different.
Step.2) We follow the rules-
If ‘A’ is any number and let x & y are the natural numbers,
then- Aˣ x Aʸ = A⁽ˣ⁺ʸ⁾
3⁸ = 3 x 3 x 3 x 3 x 3 x 3 x 3 x 3 = 6561 (Ans.)
7) Write the product of number (-8)⁵ and (-8)⁷ as single power.
Ans.) (-8)⁵ and (-8)⁷
= (-8)⁵ x (-8)⁷ = (-8) ⁵⁺⁷ = (-8)¹²
Step.1) Observe the given two-digit, where the base are the same but exponents are different.
Step.2) We follow the rules- If ‘A’ is any number and let x & y are the natural numbers,
then- Aˣ x Aʸ = A⁽ˣ⁺ʸ⁾
= (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8) x (-8)
= (- 68719476736) (Ans.)
8) Evaluate (3⁴)²
(3⁴)² = (3)⁴˟² = 3⁸
Step.1) We can observe that, there is one base two exponents
Step.2) We will follow the rules –
If ‘A’ is any number, m & n are the natural number, then-
( Aᵐ) ⁿ = Aᵐⁿ
3⁸ = 3 x 3 x 3 x 3 x 3 x 3 x 3 x 3 = 6561 (Ans.)
9) Multiply 5⁴ and 2⁴
Ans.) 5⁴ and 2⁴ = 5⁴ x 2⁴ = 10⁴
Step.1) We can observe that, in given numbers base are different but exponents are equal.
Step.2) we follow the rules as discussed below -
If ‘A’ & ‘B’ are any number and m is a natural number, then
Aᵐ x Bᵐ = (AB)ᵐ
= 10⁴ = 10 x 10 x 10 x 10
= 10000 (Ans.)
10) Explain (-5)⁵ = ?
Ans.) (-5)⁵
= (-5) x (-5) x (-5) x (-5) x (-5)
= - 3125 (Ans.)
Step.1) Here we can observe that there are single base and the exponents are shown 5 times, so we have to multiply the given base by 5 times.
Step.2) Value comes with a negative (-) sign or value because -
as pr rules (-A)ᵐ = - Aᵐ when ‘m’ is odd. 5 is odd number
(-5) x (-5) x (-5) x (-5) x (-5) = - 3125
So , -3125 is the actual/final result. (Ans.)
11) Evaluate 9⁷ / 9⁴
Ans.) 9⁷ / 9⁴
9⁷
= --------- = 9⁷⁻⁴ = 9ᶟ
9⁴
Step.1) Observe in a given fraction base are the same but exponents are different. so
Step.2) We follow the rules -
If ‘A’ is any number, m & n are the natural number, where m > n then-
Aᵐ
---------- = A ⁽ᵐˉⁿ⁾
Aⁿ
= 9ᶟ = 9 x 9 x 9 = 729 (Ans.)