If 2a - 3b = 10 and Ab = 16; Find the Value of 8a3 - 27b3. - Mathematics

If 2a - 3b = 10 and ab = 16; find the value of 8a³ - 27b³.

Sum

2a - 3b = 10
(2a - 3b)³ = (2a)³ - (3b)³ - 2(2a) (3b) (2a - 3b)
⇒ 1000 = 8a³ - 27b³ - 12(16) (10)
⇒ 8a³ - 27b³
= 1000 + 1920
= 2920.

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Chapter 4: Expansions - Exercise 4.2

Chapter 4 Expansions
Exercise 4.2 | Q 22

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