Question

2) Find the product using suitable identities: a) (5a-4b)2 b) (4a+3)2

Answer 1

Step-by-step explanation:

1. (5a - 4b)²

(a-b)² = a² + b² + 2ab

= (5a)²+(4b)²-2(5a×4b)

= 25a² + 16b²-20ab

2. (4a+3b)²

(a+b)² = a²+b²+2ab

= (4a)²+(3b)²+2(4a×3b)

= 16a²+9b²+24ab

Answer 2

GIVEN :

• (1.) ( 5a - 4b )2
• (2.) ( 4a + 3)2

TO FIND :

• Find the product of both (1.) and (2.) = ?

STEP - BY - STEP EXPLAINATION :

★ FOR (1.)

=> ( 5a - 4b ) 2

Formula used :

=> (a - b)² = a² + b² + 2ab

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=> (5a - 4b ) 2

=> ( 5a )² + (4b)² - ( 5a × 4b )

=> 25a² + 16b² - 20ab

★ FOR (2.)

=> ( 4a + b ) ²

Formula used :

=> (a + b ) ² = a² + b² + 2ab

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=> ( 4a + b )²

=> ( 4a ) ² + ( 3b )² + 2( 4a × 3b )

=> 16a² + 9b² + 24ab