54
If a + b = 4 then the value of a3 + b3 + 12ab - 64 is:
- A24
- B25
- C0
- D27
Answer not set
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0
CCommunity
(a + b)3 = a3 + b3 + 3ab(a + b) ----(i)
Given that, a + b = 4, putting this value of (a + b) in eq. (i)
∴ 64 = a3 + b3 + 3ab(4)
⇒ a3 + b3 + 12ab – 64 = 0
Given that, a + b = 4, putting this value of (a + b) in eq. (i)
∴ 64 = a3 + b3 + 3ab(4)
⇒ a3 + b3 + 12ab – 64 = 0