Question

1. Find the square of:
(i) 2a + b
(ii) 3a + 7b
(iii)
3a - 4b​

Answer 1

Answer:

(i) 4a^2 + b^2 + 4ab

(ii) 9a^2 + 49b^2 + 42ab

(iii) 9a^2 + 16b^2 - 24ab

Step-by-step explanation:

By using the formulae

(a+b)^2 = a^2 + b^2 +2ab

and

(a-b)^2 = a^2 + b^2 - 2ab

We can obtain the answers...

Answer 2

Answers:

Solution:

1) 2a + b

Using the identity: (a+b)² = a² + b² + 2ab

= (2a)² + (b)² + 2 × 2a × b

= 4a² + b² + 4ab

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2) 3a + 7b

Using the identity: (a+b)² = a² + b² + 2ab

= (3a)² + (7b)² + 2 × 3a × 7b

= 9a² + 49b² + 42ab

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3) 3a - 4b

Using the identity: (a - b)² = a² + b² - 2ab

= (3a)² + (4b)² - 2 × 3a × 4b

= 9a² + 16b² - 24ab

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Final answers:

1) 4a² + b² + 4ab

2) 9a² + 49b² + 42ab

3) 9a² + 16b² - 24ab