Question

19. Simplify: (3x – 4y)3– (3x + 4y)3​

Answer 1

$\textbf{Given:}$

$\mathsf{(3x-4y)^3-(3x+4y)^3}$

$\textbf{To simplify:}$

$\mathsf{(3x-4y)^3-(3x+4y)^3}$

$\textbf{Solution:}$

$\textsf{Consider,}$

$\mathsf{(3x-4y)^3-(3x+4y)^3}$

$\mathsf{Using,}$

$\boxed{\mathsf{(a+b)^3=a^3+b^3+3a^2b+3ab^2}}$

$\boxed{\mathsf{(a-b)^3=a^3-b^3-3a^2b+3ab^2}}$

$\mathsf{=[(3x)^3-(4y)^3-3(3x)^2(4y)+3(3x)(4y)^2]-[(3x)^3+(4y)^3+3(3x)^2(4y)+3(3x)(4y)^2]}$

$\mathsf{=[27x^3-64y^3-108x^2y+144y^2]-[27x^3+64y^3+108x^2y+144xy^2]}$

$\mathsf{=27x^3-64y^3-108x^2y+144y^2-27x^3-64y^3-108x^2y-144xy^2]}$

$\mathsf{=-128y^3-216x^2y}$

$\implies\boxed{\mathsf{(3x-4y)^3-(3x+4y)^3=-128y^3-216x^2y}}$

$\textbf{Find more:}$

[(0.7)⁴-(0.5)⁴] / [(0.7)³-(0.5)³]

https://brainly.in/question/38897903

Answer 2

Answer:

-128y³-216x²y

Step-by-step explanation:

[27x³-64y³-108x²y+144y²]-[27x³+64y³+108x²y+144y²]

=-128y³-216x²y