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Question
Find the cube of: `(2"m")/(3"n") + (3"n")/(2"m")`
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Solution
`((2"m")/(3"n") + (3"n")/(2"m"))^3`
= `((2"m")/(3"n"))^3 + ((3"n")/(2"m"))^3 + 3((2"m")/(3"n"))((3"n")/(2"m"))((2"m")/(3"n") + (3"n")/(2"m"))`
= `(8"m"^3)/(27"n"^3) + (27"n"^3)/(8"m"^3) + (2"m")/"n" + (9"n")/(2"m")`.
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