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Question
If a + b = 8 and ab = 6, find the value of a3 + b3
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Solution
In the given problem, we have to find the value of `a^3 +b^3`
Given `a+b = 8.ab = 6`
We shall use the identity `a^3 + b^3 = (a+b)^3 ab(a+b)`
`a^3 + b^3 = (a+b)^3- 3ab (a+b)`
`a^3 +b^3 = a(8)^3 - 3 3 xx 6 (8)`
`a^3 +b^3 = 512 - 144`
`a^3+b^3 = 368`
Hence the value of i`a^3 +b^3` is 368 .
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