Question

class-9
icse question

Expand the following:

(5ab + 2)³​

Answer 1

As we know the identity (a+b)³ = a³ + 2a²b + 2ab² + b³

so now

(5ab + 2)³

= (5ab)³ + 2(5ab)²(2) + 2(5ab)(2)² + (2)²

= 125ab³ + 100ab² + 40ab + 4

Mark me as the brainliest

Answer 2

Answer:

Use the formula of $(A+B)^{3}$ = $a^{3} + b^{3} + 3ab(a+b)$

Step-by-step explanation:

$(5ab+2)^{3} = (5ab)^{3} + 2^{3} + 3(5ab)(2)( 5ab + 2)\\125a^{3}b^{3} + 8 + 30ab(5ab + 2)\\125a^{3}b^{3} + 8 + 30ab* 5ab + 30ab * 2\\125a^{3}b^{3} + 8 + 150a^{2}b^{2} + 60ab$