if x plus 1by x is 7then xcube plus 1by x cube is equal to

1.	if x plus 1by x is 7then xcube plus 1by x cube is equal to
Answer» x+1/x=7 ( taking cube on both sides) then (x+1/x )cube=7cube ,xcube+1/xcube+3 (x+1/x)=343 then we get xcube +1/x cube= 343-21so we get xcube +1/xcube=322 217/36

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