Question

expansion (4/9m-7/3n)^3​

Answer 1

Answer:

64/729 m³ + 343/27 n³ + 28/9 m²n - 28/9 mn²

Step-by-step explanation:

For this question, we use the identity (a - b)³=a³ - b³ - 3a²b + 3ab².

(4/9m-7/3n)³ = (a - b)³

Comparing, 4/9 m = a        AND        -7/3 n = b

=> (4/9 m)³ - (-7/3 n)³ - 3(4/9 m)²(-7/3 n) + 3(4/9 m)(-7/3 n)²

=> 64/729 m³ + 343/27 n³ + 28/9 m²n - 28/9 mn²