NCERT Solutions Class 8 Maths Ganita Prakash Chapter 2 — Power Play#

Chapter 2 of Ganita Prakash Part I is about exponents: writing repeated multiplication as a power, the laws of exponents, negative powers, and scientific notation for very large and very small numbers. It also shows how fast numbers grow when they keep multiplying.

Exercises#

• Figure it Out — Page 22 — Exponential form, prime factors as powers, numerical values of powers (3 questions)
• Figure it Out — Page 44 — Units digits, laws of exponents, always/sometimes/never true, scientific notation and estimation (14 questions)

What you will learn#

• $n^a$ means $n$ multiplied by itself $a$ times; $n$ is the base and $a$ the exponent.
• The laws of exponents, and what zero and negative exponents mean.
• Writing numbers in scientific notation, $x \times 10^y$ with $1 \le x < 10$.
• Estimating huge quantities with powers of 10.

Key formulas and results#

• $n^a \times n^b = n^{a + b}$ and $n^a \div n^b = n^{a - b}$
• $(n^a)^b = n^{a \times b}$ and $n^a \times m^a = (n \times m)^a$
• $n^0 = 1$ and $n^{-a} = \dfrac{1}{n^a}$ (for $n \ne 0$)

Read and revise#

• NCERT Class 8 Maths Chapter 2 (PDF) — the Ganita Prakash Part I chapter itself.
• All Class 8 Maths chapters from Ganita Prakash Part I and Part II.

Frequently asked questions#