Question

(m+n)³ + (m-n)³ pls give me answers ​

Answer 1

Answer:

(m+n)^3+(m-n)^3

={(m+n)+(m-n)}}^3-3(m+n)(m-n){(m+n)(m-n)}

=(m+n+m-n)^3-3(m^2-n^2)(m+n+m-n)

=(2m)^3-3(m^2-n^2).2m

=8m^3-6m^3+6mn^2

=2m^3+6mn^2

=2m(m^2+3n^2)

Answer 2

Answer:

Given :-

➪ (m + n)³ + (m - n)³

Solution :-

➪ (m + n)³ + (m - n)³

➭ {(m + n) + (m - n)} {(m + n)² - ( m + n) × (m - n) + (m - n)²}

➭ (m + n + m - n) {(m)² + 2 × m × n + (n)² - m² - mn + mn - n² + (m)² - 2 × m × n + (n)²}

➭ (m + m + n - n) {(m² + 2mn + n²) - (m² - n² + mn - mn) + (m² - 2mn + n²)}

➭ (2m) (m² - m² + m² + n² + n² + n² + 2mn - 2mn)

➭ 2m (m² + 3n²)

➭ 2m³ + 6mn²

∴ The answer of this question is 2m³ + 6mn²

Formula used :-

➪ a³ + b³

➭ (a + b) (a² - ab + b²)