NCERT Solutions for Class 8 Maths Chapter 6 We Distribute, Yet Things Multiply - Exercise 6.2
Mastering the expansion of algebraic terms is simple with our NCERT Solutions for Class 8 Maths Ch 6: We Distribute, Yet Things Multiply – Exercise 6.2. This exercise focuses on the multiplication of monomials. You will learn how to combine numerical coefficients and apply the laws of exponents to variables.
Class 8 Math Lessons (Ch 6): Learn to Multiply Algebraic Terms with Ease! The solutions to Exercise 6.2 will be presented in a step-by-step approach to help students find the product of two or more monomials and calculate the area of rectangles using algebraic dimensions. These solutions follow CBSE Guidelines to ensure accuracy in fundamental algebraic operations.
1.0Download NCERT Solutions for Class 8 Maths Chapter 6 We Distribute, Yet Things Multiply Ex 6.2 : Free PDF
Our easy-to-follow NCERT Solutions for Class 8 Maths Chapter 6 Exercise 6.2 are available for download as a PDF. Perfect for offline study and quick reference.
2.0Detailed NCERT Class 8 Maths Chapter 6 Solutions of Exercise 6.1
1.Which is greater: (a−b)2 or (b−a)2 ? Justify your answer.
Sol. Here, (a−b)2=a2+b2−2ab
and (b−a)2=b2+a2−2ab
b2+a2=a2+b2 and ba=ab
(b−a)2=a2+b2−2ab
Comparing (1) and (2), we get (a−b)2=(b−a)2
2. Express 100 as the difference of two squares.
Sol. a2−b2=100
(a+b)(a−b)=100
[100= 1×100,2×50,4×25,5×20,10×10 ]
We can take anyone
Let us take 50×2=100
Hence,
(a+b)(a−b)=50×2
a+b=50
a−b=2
Adding (1) and (2)
2a = 52
⇒a=26
Substituting a = 26 in (1)
26+b=50
⇒b=50−26=24
Let us check 262−242=676−576=100
Hence, 262−242=100
3. Find 4062,722,1452,10972, and 1242 using the identities you have learnt so far.
Sol. (i) 4062=(400+6)2
=4002+2×400×6+62=160000+4800+36=164836
(ii) 722=(50+22)2
=502+2×50×22+222=2500+2200+484=5184
(iii) 1452=(150−5)2
=1502−2×150×5+52=22500−1500+25=21025
(iv) 10972=(1100−3)2
=11002−2×1100×3+32=1210000−6600+9=1203409
(v) 1242=(100+24)2
4.Do Patterns 1 and 2 hold only for counting numbers? Do they hold for negative integers as well? What about fractions? Justify your answer.
Sol. 2(a2+b2)=(a+b)2+(a−b)2
Case-I
Let
a=4, b=2
LHS =2(42+22)=2×(16+4)=40
RHS =(4+2)2+(4−2)2=62+22=36+4=40
∴ Pattern 1 holds for counting numbers.
Case-II
Let
a=−4, b=−2
LHS =2((−4)2+(−2)2)
=2×(16+4)
=2×20
=40
RHS =(−4+(−2))2+(−4−(−2))2
=(−4−2)2+(−4+2)2
=(−6)2+(−2)2
=36+4
=40
LHS = RHS
∴ Pattern 1 holds for negative integers also.
Case-III
Let a=21, b=31
LHS =2((21)2+(31)2)=2(41+91)=2×3613=1813RHS=(21+31)2+(21−31)2=(65)2+(61)2=3625+361=3626=1813
The pattern holds for fractions also.
Pattern 2
a2−b2=(a+b)(a−b)
Case I
Let a=5, b=3
LHS =52−32=25−9=16
RHS =(5+3)(5−3)=8×2=16
∴ LHS = RHS
∴ Pattern 2 holds for counting numbers
Case II
Let a=−5, b=−3
Now, LHS =(−5)2−(−3)2=25−9=16
And RHS =[(−5)+(−3)][(−5)−(−3)]
=(−5−3)(−5+3)
=(−8)(−2)
= 16
∴ LHS = RHS
∴ Pattern 2 hold for negative integers also.
Case III
Let a=21, b=31
LHS =(21)2−(31)2
=41−91
=369−4
=365
And RHS =(21+31)(21−31)=(63+2)(63−2)=65×61=365
∴ LHS = RHS
∴ Pattern 2 holds for fractions also.
3.0Key Concepts of Chapter 6 We Distribute, Yet Things Multiply Exercise 6.2
- Multiplying Two Monomials: To find the product, multiply the numerical coefficients together and the algebraic parts (variables) together.
- Laws of Exponents: Remember that when multiplying variables with the same base, you add their powers: xa×xb=xa+b.
- Area as a Product: The area of a rectangle is Length x Breadth. If the dimensions are given as monomials, the area is their algebraic product.
- Volume of a Rectangular Box: Volume is calculated as length x breadth x height. This involves finding the product of three monomials.
4.0NCERT Solutions for Class 8 Maths Chapter 6 We Distribute, Yet Things Multiply : All Exercises
5.0Benefits of NCERT Solutions for Class 8 Maths Chapter 6 Exercise 6.2
- Conceptual Clarity: Helps students understand that the order of multiplication (commutative property) does not change the result.
- Pattern Recognition: Reinforces the use of exponents when the same variable appears multiple times in a product.
- Application-Based: Connects algebra to geometry by solving for area and volume.