Question

please solve this both 10 and 11​

Answer 1

Solution :

10.

Given 3x - 2y = 11, xy = 12

So, 27x³ - 8y³

= (3x)³ - (2y)³

= (3x - 2y)³ + (3 * 3x * 2y) (3x - 2y)

= (3x - 2y)³ + 18xy (3x - 2y)

= 11³ + (18 * 12 * 11)

= 1331 + 2376

= 3707

11.

Given, x - 1/x = 7

So, x³ - 1/x³

= (x - 1/x)³ + (3 * x * 1/x) (x - 1/x)

= 7³ + 3 * 7

= 343 + 21

= 364

Identity Rules :

  1. a³ + b³ = (a + b)³ - 3ab (a + b)

 2. a³ - b³ = (a - b)³ + 3ab (a - b)

Answer 2

That's the answer hope it helps you. GO BANKAI