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Question
If a + b = 10 and ab = 21, 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 = 10, ab = 21`
We shall use the identity `(a+b)^3 = a^3 +b^3 +3ab(a+b)`
Here putting, `a+b = 10,ab= 21`
`(10)^3 = a^3+ b^3 +3 (21)(10)`
` 1000 = a^3 +b^3 +630`
`1000 - 630 = a^3 +b^3`
`370 = a^3 + b^3`
Hence the value of `a^3 +b^3` is 370.
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