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Question
If `"a" + 1/"a"` = 6, then find the value of `"a"^3 + 1/"a"^3`
Sum
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Solution
`"a" + 1/"a"` = 6 ...[a3 + b3 = (a + b)3 – 3ab (a + b)]
`"a"^3 + 1/"a"^3 = ("a" + 1/"a")^3 - 3"a" xx 1/"a"("a" + 1/"a")`
= 63 – 3(6)
= 216 – 18
= 198
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