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RS Aggarwal Class 8 Chapter 2 Solutions (Exponents)

RS Aggarwal Class 8 Maths Solutions Chapter 2 ‘Exponents’ are here to help you solve all the exercises of the chapter. RS Aggarwal Class 8 Maths Solutions for Chapter 2 includes practice questions on topics exponents and powers, how to express exponents in the standard form, laws of exponents, expressing decimal numbers in exponential form, negative exponents, and comparison between numbers using exponents. 

This chapter is based on the CBSE Class 8 Maths syllabus and provides 37 practice questions that are divided into 3 sets of exercises. Practising this chapter from RS Aggarwal book will help you revise the concepts that you have learned in class and will make it easier for you to prepare this chapter for your exams. 

Some of the questions given in the exercises are difficult to solve as they involve multiple steps, but our solutions will help you understand how to solve them in the easiest way. Our subject matter experts have included stepwise explanations in the solutions so all your doubts would be resolved in minutes. Here are some important topics related to RS Aggarwal Class 8 Maths Chapter 2 ‘Exponents’ that you must read. Then we also have listed the highlights of the exercises of the chapter. 

Important Topics for RS Aggarwal Class 8 Maths Solutions Chapter 2: Exponents

Exponents and Base

If a number is given in the form of ‘Xy’ then, X is called the ‘base’ and Y is called the ‘exponent’. Exponents can be positive or negative. We can convert a negative exponent into a positive exponent in the following way:

x-y=(1/x)y

For Example: 77-15 = (1/77)15, (233/77)-22 = (77/233)22

Laws of Exponents 

There are certain rules for performing arithmetic operations with exponents: 

  • When we multiply two exponential numbers with the same base, their exponents are added:

Xy x Xw =Xy+w

For Example 58 x 519 = 5(8+19) = 527

  • When we multiply two exponential numbers with a different base and same exponents, then the exponents are combined: Xy x By =(X x B)y

For Example  58 x 28 =(5 x 2)8

  • When we divide two exponential numbers with the same base, their exponents are subtracted: Xy/Xw =Xy-w

For Example 58/519 = 5(8-19) = 5-11

  • When we divide two exponential numbers with a different base and same exponents, then the exponents are combined: Xy/Wy   = (X/W)y

For Example: 58/28= (5/2)8

  • Any number with an exponents zero is equal to 1: w0 = 1

For Example: 30 = 1, 5670 = 1, 444335450 = 1

Why Do We Need Exponential Numbers

You must be thinking that why do we need to write 22 when we can simply write 4 in its place. Well, calculating, managing and remembering small numbers is easy but when it comes to big numbers, you might not be able to remember them. 

For example, do you know that the mass of the earth is 5,976,000,000,000,000,000,000,000 kg. It might be tough for anyone to remember the number of zeros here. But, when we write that the mass of the earth is around 5.976 x 1024 kg, it is much easier to remember that. 

Converting Large Numbers into Exponential Form 

Suppose you have a number 189,000,000,000,000 that you need to convert to standard form. The leftmost digit of this number is ‘1’. After that, there are 14 digits. So, the exponent here would be ‘14’. Then,  we will place a decimal point after the left-most digit and keep the non-zero digits as it is. We will remove the zeroes and represent the number as 1.89 X 1014 

Similarly, for the number 16783000, the standard representation will be 1.6783 X 107

If we have a decimal number 0.0000028474 then, we will represent the number in standard form as 2.8474 x 10-6. Here, we have moved the decimal point 6 places forward and hence we are representing the exponent as negative 6. 

Exercise Discussion for RS Aggarwal Class 8 Maths Solutions Chapter 2: Exponents

  1. There are three exercises in this chapter of RS Aggarwal Solutions. Exercise 2A is very easy. There are 13 questions in this exercise in which you have to evaluate the given expressions. These questions are based on multiplication and division of exponential numbers. 
  2. Exercise 2B has 7 questions in which you have to write the numbers in standard form and vice-versa. You must be very careful with the calculations in this exercise. 
  3. Exercise 2C has 17 multiple-choice questions based on the concepts discussed in the chapter. This is a miscellaneous exercise that includes slightly tough questions. 

Why Use RS Aggarwal Maths Class 8 Solutions Chapter 2: Exponents by Instasolv

  • Solving RS Aggarwal Chapter 2 exercises for Class 8 Maths is now super-easy for you as our answers will guide you with all the formulae and properties to be used. 
  • Our subject matter experts are up-to-date with the latest CBSE guidelines and have based our solutions on that. 
  • This means you can easily refer to these solutions and prepare well for your exams. 
  • All the tough concepts of the chapter are explained in simple form in our solutions.