Question

expand the question of (7x+8y)cube

Answer 1

it's a answer
I hope it helps you

Answer 2

Answer:

$(7x+8y)^3=343x^3+512y^3+1176x^2y+1344xy^2$  

Step-by-step explanation:

Given : Expression $(7x+8y)^3$

To find : Expand the expression ?

Solution :

We know the cubic formula,

$(a+b)^3=a^3+b^3+3a^2b+3ab^2$

Substitute, a=7x and b=8y

$(7x+8y)^3=(7x)^3+(8y)^3+3\times(7x)^2\times(8y)+3\times(7x)\times(8y)^2$

$(7x+8y)^3=343x^3+512y^3+3\times 49x^2\times 8y+3\times7x\times64y^2$

$(7x+8y)^3=343x^3+512y^3+1176x^2y+1344xy^2$

Therefore, The expansion is

$(7x+8y)^3=343x^3+512y^3+1176x^2y+1344xy^2$