Question

expand: 1)(⅔a+1)³
2) (5x-3y)³​

Answer 1

Step-by-step explanation:

1. (⅔a+1)³

soln,

= (⅔a)³ + 3.(⅔a)².1 + 3.⅔a.1² + 1³

= 8a³/27 + 12a²/9 + 6a/3 +1

2. (5x-3y)³

soln,

= (5x)² - 3.(5x)².3y + 3.5x.(3y)² - (3y)³

= 25x² - 225x²y + 135xy² - 27y³

Note : Just apply formula of (a+b)³ and (a-b)³