×square + 1/xsquare=27.Find 3xcube +5x - 3/xcube -5/x
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x²+1/x² = 27
x²+1/x² - 2 = 25
(x-1/x)² = 25
(x-1/x) = 5
3x³ - 3/x³ = 3(x³-1/x³) = 3 (x-1/x) (x²+1+1/x²) = 3(5)(28) = 420
5x-5/x = 5(x-1/x) = 5(5) = 25
Add both of them, the result is 445
x²+1/x² - 2 = 25
(x-1/x)² = 25
(x-1/x) = 5
3x³ - 3/x³ = 3(x³-1/x³) = 3 (x-1/x) (x²+1+1/x²) = 3(5)(28) = 420
5x-5/x = 5(x-1/x) = 5(5) = 25
Add both of them, the result is 445
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