Carry out the multiplication of the expressions in each of the following pairs
(i) 4p, q + r   (ii) ab, a - b   (iii) a + b, 7a²b²
(iv) a² - 9, 4a   (v) pq + qr + rp, 0

Solution:

Multiplication of two algebraic expressions or variable expressions involves multiplying two expressions that are combined with arithmetic operations such as addition, subtraction, multiplication, division, and contain constants, variables, terms, and coefficients.

(i) (4p) × (q + r ) = (4p × q) + (4p × r) = 4pq + 4pr

(ii) (ab) × (a - b) = (ab × a) + [ab × (- b)] = a²b - ab²

(iii) (a + b) × (7a² b² ) = (a × 7a²b² ) + (b × 7a²b² ) = 7a³b² + 7a²b³

(iv) (a² - 9) × (4a) = (a² × 4a) + [(- 9) × (4a)] = 4a³ - 36a

(v) ( pq + qr + rp) × 0 = ( pq × 0) + (qr × 0) + (rp × 0) = 0

☛ Check: NCERT Solutions for Class 8 Maths Chapter 9

Video Solution:

Carry out the multiplication of the expressions in each of the following pairs. (i) 4p, q + r (ii) ab, a - b (iii) a + b, 7a²b² (iv) a² - 9, 4a (v) pq + qr + rp, 0

Maths NCERT Solutions Class 8 Chapter 9 Exercise 9.3 Question 1

Summary:

The multiplication of the expressions in each of the following pairs. (i) 4p, q + r (ii) ab, a - b (iii) a + b, 7a²b² (iv) a² - 9, 4a (v) pq + qr + rp, 0 are as follows: (i) 4pq + 4pr, (ii) a²b - ab², (iii) 7a³b² + 7a²b³, (iv) 4a³ - 36a, (v) 0

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