This set of Class 8 Maths Chapter 12 Multiple Choice Questions & Answers (MCQs) focuses on “Laws of Exponents”.
1. Find the value of \(\frac{1}{8^{-2}}\).
a) \(\frac{1}{16}\)
b) \(\frac{1}{64}\)
c) 16
d) 64
View Answer
Explanation: \(\frac{1}{a^{-m}}\) = am
⇒ \(\frac{1}{8^{-2}}\) = 82 = 64.
2. What is 2-3?
a) \(\frac{1}{4}\)
b) \(\frac{1}{8}\)
c) 4
d) 8
View Answer
Explanation: a-m = \(\frac{1}{a^m}\)
⇒ 2-3 = \(\frac{1}{2^3}\) = \(\frac{1}{8}\).
3. Find the value of 16-2 × 1614.
a) 1612
b) 16-12
c) 1614
d) 16-14
View Answer
Explanation: am × an = am + n
⇒ 16-2 × 1614 = 16-2 + 14 = 1612.
4. Evaluate \((\frac{21^{29}}{21^5})\).
a) 2125
b) 21-25
c) 2124
d) 21-24
View Answer
Explanation: \(\frac{a^m}{a^n}\) = am – n
⇒ \((\frac{21^{29}}{21^5})\) = 2129 – 5 = 2124.
5. Match the pairs.
| A | B |
| 1) 23 × 83 | a. 1 |
| 2) \(\frac{8^3}{2^3}\) | b. 163 |
| 3) (23)0 | c. 43 |
| d. 8 |
a) 1-b, 2-c, 3-d
b) 1-b, 2-c, 3-a
c) 1-c, 2-b, 3-a
d) 1-c, 2-b, 3-d
View Answer
Explanation: am × bm = (ab)m
⇒ 23 × 83 = (2 × 8)3 = 163
Now, \(\frac{a^m}{b^m} = (\frac{a}{b})^m\)
⇒ (\(\frac{8}{2})^3\) = 43
Also, (am)n = amn, a0 = 1
⇒ (23)0 = 23 × 0 = 20 = 1.
6. Find the value of (23)2.
a) 128
b) 16
c) 32
d) 64
View Answer
Explanation: (am)n = amn
⇒ (23)2 = 26 = 64.
Sanfoundry Global Education & Learning Series – Mathematics – Class 8.
To practice all chapters and topics of class 8 Mathematics, here is complete set of 1000+ Multiple Choice Questions and Answers.
