Express the following numbers in the exponential form:
1728
We prime factorize the number
1728 = 33× 26
⇒ 1728 = 33× 43
Since the powers are same so the bases can be multiplied
⇒ 1728 = 123
Express the following numbers in the exponential form:
We prime factorize the number 512
512 = 29
Since reciprocal of a number results in negative power,
So = 2-9
Express the following numbers in the exponential form:
0.000169.
We prime factorize the number 169
169 = 132
So we can say that
0.000169 = 132× 10-6
⇒ 0.000169 = (13× 10-3)2
⇒ 0.000169 = 0.0132
Write the following numbers using base 10 and exponents:
12345
The number can be expanded by expressing the number in terms of its digits and multiplying each digit with 10 raised to a specific power according to its place value
12345 = 1×104 + 2×103 + 3×102 + 4×10 + 5
Write the following numbers using base 10 and exponents:
1010.0101
Write the following numbers using base 10 and exponents:
0.1020304
Find the value of (−0.2)-4
Since the power is negative so
Simplify:
31 × 32 × 33 × 34 × 35 × 36 .
Since the bases are same so the powers can be added
31 × 32 × 33 × 34 × 35 × 36 = 3(1 + 2 + 3 + 4 + 5 + 6)
⇒ 31 × 32 × 33 × 34 × 35 × 36 = 321
Simplify:
22 × 33 × 24 × 35 × 36.
Since there are two bases so their powers can be separately added.
22 × 33 × 24 × 35 × 36 = 2(2 + 4) × 3(3 + 5 + 6)
⇒ 22 × 33 × 24 × 35 × 36 = 26 × 314
How many zeros are there in 104 × 103 × 102 × 10?
Since the bases are same so the powers can be added
104 × 103 × 102 × 10 = 10(4 + 3 + 2 + 1)
⇒ 104 × 103 × 102 × 10 = 1010
Since the power of 10 is 10 so there are 10 zeroes.
Which is larger: (53 × 54 × 55 × 56) or (57 × 58)?
53 × 54 × 55 × 56 = 5(3 + 4 + 5 + 6)
⇒ 53 × 54 × 55 × 56 = 518
57 × 58 = 5(7 + 8)
⇒ 57 × 58 = 515
Since the power of 5 in 53 × 54 × 55 × 56 is greater so 53 × 54 × 55 × 56 is greater than 57 × 58
Simplify:
10−1 × 102 × 10−3 × 104 × 10−5 × 106;
Since the bases are same so their powers are solved algebraically
10−1 × 102 × 10−3 × 104 × 10−5 × 106 = 10(-1 + 2-3 + 4-5 + 6)
On solving we get,
⇒ 10−1 × 102 × 10−3 × 104 × 10−5 × 106 = 103
Simplify:
.
Since the denominator and numerator have common base so their powers can be subtracted
Which is larger: (34 × 23) or (25 × 32)?
We divide the two expressions
Since the denominator and numerator have common base so their powers can be subtracted
Since the fraction is greater than 1 so (34 × 23) is greater than (25 × 32)
Suppose m and n are distinct integers. Can be an integer? Give reasons.
We divide the two expressions
Since the denominator and numerator have common base so their powers can be subtracted
Since m and n are two distinct integers so the power can never become 0 and hence the fraction can never an integer.
Suppose b is a positive integer such that is also an integer. What are the possible values of b?
Since is an integer so
the numerator must be greater than denominator
So b has to be either 1,2 or 4 to become an integer.
Simplify:
Simplify:
Can you find two integers m,n such that 2m + n = 2mn ?
2m + n = 2mn
⇒ m + n = mn
Let m = n
So we get
2m = m2
⇒ m = 2
Since m = n, so
n = 2
If (2m)4 = 46, find the value of m.
(2m)4 = 46
⇒ (4m)2 = 46
Since the bases are same so their powers can be equated
2m = 6
⇒ m = 3
Simplify:
Since the bases are common in numerator and denominator so their powers are subtracted
Simplify:
Since the bases are common in numerator and denominator so their powers are subtracted
Simplify:
Is an integer? Justify your answer.
Since after reducing the expression there is a 5 in the denominator but no multiple of 5 in the numerator so it is not an integer
Which is larger : (100)4 or (125)3?
We divide the two numbers
Since the numerator is greater than the denominator so 1004 is greater than 1253
Simplify:
Since bases are same so the powers can be subtracted
Simplify:
(1.8)6 × (4.2)-3
(1.8)6 × (4.2)-3 = (18×10-1)6×(42×10-1)-3
⇒ (1.8)6 × (4.2)-3 = (32×2×10-1)6×(7×3×2×10-1)-3
⇒ (1.8)6 × (4.2)-3 = 312×26×10-6×7-3×3-3×2-3×103
⇒ (1.8)6 × (4.2)-3 = 39×23×7-3×10-3
Simplify:
Can it happen that for some integer m ≠ 0, ?
Since the bases are same so the powers can be equated
2m = m2
⇒ m = 2
So it can happen when m = 2
Find all positive integers m,n such that (3m)n = 3m × 3n.
(3m)n = 3m × 3n
⇒ 3mn = 3m + n
Since the bases are same so the powers can be equated
mn = m + n
Let m = n
⇒ m2 = 2m
⇒ m = 2
Answer: m = 2, n = 2
Use the laws of exponents and simplify.
126 = (4×3)6
⇒ 126 = 212×36
On prime factorizing 162 we get
162 = 2× 34
Use the laws of exponents and simplify.
Use the laws of exponents and simplify.
What is the value of
Simplify:
Find the value of each of the following expressions:
(32)2 − ((−2)3)2 − ( − (52))2 ;
(32)2 = 92 = 81
((−2)3)2 = (-8)2 = 64
( − (52))2 = (-25)2 = 625
So the value of the expression is
(32)2 − ((−2)3)2 − ( − (52))2 = 81-64-625 = -608
Find the value of each of the following expressions:
((0.6)2)0 − ((4.5)0)−2 ;
The value of any number raised to the power zero is always 1
((0.6)2)0 = 1
(4.5)0 = 1
⇒ 1-2 = 1
So the solution of the expression is
((0.6)2)0 − ((4.5)0)−2 = 1-1 = 0
Find the value of each of the following expressions:
(4-1)4 = 4-4
⇒ (4-1)4 = 2-8
(8-2)5 = (2-6)5
⇒ (8-2)5 = 2-30
(642)3 = (212)3
(642)3 = 236
= 2-8×25×2-12×2-30×236
⇒ = 2-9
The value of (3m)n, for every pair of integers (m,n), is
A. 3m+n
B. 3mn
C. 3mn
D. 3m + 3n
Using the third law of exponents, If a ≠0 is a number and m, n are integers, then(am)n= amn
So, (3m)n = 3mn
If x,y, are nonzero real numbers, then
equals
A. 1
B. x ⋅ y
C. x ⋅ y
D. 1/xy
For a number a ≠ 0, we define
It is given that x,y, are nonzero real numbers,
If 2x − 2x−2 = 192, the value of x is
A. 5
B. 6
C. 7
D. 8
Given 2x − 2x−2 = 192
⇒2x–2x.2−2 = 192
Taking 2x common from both the terms,
⇒2x (1 - 2−2) = 192
For a number a ≠ 0and natural number n, we define
⇒2x = 64× 4
⇒2x = 26 × 22
For any a ≠ 0, and integers m,n, am × an = am+n
⇒2x = 28
Hence, x = 8
The number is equal to
A. 66
B.
C.
D.
Using the third law of exponents, If a ≠0 is a number and m, n are integers, then (am)n= amn
For a number a ≠ 0, we define
For any a ≠ 0, and integers m,n, am × an = am+n
The number of pairs positive integers (m,n)such that mn =25 is
A. 0
B. 1
C. 2
D. more than 2
Given mn =25
⇒mn = 52
⇒ (m, n) = (5, 2)
Hence, only 1 such pair of positive integers is possible.
The diameter of the Sun is 1.4 × 109 meters and that of the Earth is about 1.2768 × 107 meters. Find the approximate ratio of the diameter of the Sun to that of the Earth.
Given the diameter of the Sun = 1.4 × 109 meter
And the diameter of the Earth is = 1.2768 × 107 meters
Ratio of the diameter of the sun and that of the earth =
For any number a ≠ 0 and positive integers m and n, not necessarily distinct,
Ratio of the diameter of the sun and that of the earth =
Ratio of the diameter of the sun and that of the earth =
Find the value of each of the following expressions:
{Using For a number a ≠ 0, we define
}
Find the value of each of the following expressions:
Using the third law of exponents, If a ≠0 is a number and m, n are integers, then (am)n= amn
Using For a ≠0 and b ≠ 0, and integer m,
(a × b)m = am × bm
Using For any a ≠ 0, and integers m,n,
am × an = am+n
Find the value of each of the following expressions:
Using For a ≠0 and b ≠ 0, and integer m,
(a × b)m = am × bm
Using For any a ≠ 0, and integers m, n,
am × an = am+n
How many digits are there in the number 23 × 54 × 205?
23 × 54 × 205 = 23 × 54 × (4× 5)5
Using For a ≠0 and b ≠ 0, and integer m,
(a × b)m = am × bm
⇒23 × 54 × 205 = 23 × 54 × 45× 55
⇒23 × 54 × 205 = 23 × 54 × (22 )5× 55
Using third law of exponents, If a ≠0 is a number and m, n are integers, then (am)n= amn
⇒23 × 54 × 205 = 23 × 54 × 210× 55
Using For any a ≠ 0, and integers m, n,
am × an = am+n
⇒23 × 54 × 205 = 23+10 × 54+5
⇒23 × 54 × 205 = 213 × 59
We know that 2× 5 = 10
So, 23 × 54 × 205 = (29 × 59)× 24
⇒23 × 54 × 205 = 109 × 16
⇒23 × 54 × 205 =16000000000
Hence, there are 11 digits in the given number.
If a7 = 3, find the value of .
Given: a7 = 3
{Using the third law of exponents, If a ≠0 is a number and m, n are integers, then (am)n= amn}
{UsingFor any a ≠ 0, and integers m, n,
am × an = am+n}
For any number a ≠ 0 and positive integers m and n, not necessarily distinct,
If 2m × a2 = 28, where a,m are positive integers, find all possible values of a + m.
Given: 2m × a2 = 28
⇒2m × a2 = 28× 12
Then a + m = 8 + 1 = 9
Also, 2m × a2 = 24 × 42
Then a + m = 4 +4 = 8
Similarly, 2m × a2 = 22× 82
Then a + m = 2 +8 = 10
Suppose 3k × b2 = 64 for some positive integers k, b. Find all possible values of k + b.
Given: 3k × b2 = 64
⇒3k × b2 = (2× 3)4
Using For a ≠0 and b ≠ 0, and integer m,
(a × b)m = am × bm
⇒3k × b2 = 24× 34
⇒3k × b2 = 42× 34
On comparing,
k = 4, b = 4
⇒ k+b = 8
Find the value of .
Using the third law of exponents, If a ≠0 is a number and m, n are integers, then (am)n= amn
Using For any a ≠ 0, and integers m, n,
am × an = am+n
A person had some rupees which is a power of 5. He gave a part of it to his friend which is also a power of 5. He was left with ₹ 500. How much did money he have?
Let the money he have be Rs 5x and that he gave to his friend be Rs 5y, such that x>y.
According to the question,
5x - 5y = 500
We can see from the equation that 5x> 500 because 500 is the money that he is left with.
So 5x = 625
⇒ x = 4
Then 625 - 5y = 500
⇒5y = 125
⇒ y = 3
So, the money he had = Rs 625 and that he gave to his friend = Rs 125