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It’s in my head.
Nice video
1/(x^3)-1/(x+1)^3=7/8 x=-2 x=1 x=(-1/2)±(1/14)iSqrt[147±28Sqrt[21] ]=-0.5±0.1(0.714285 recurring)iSqrt[147±28Sqrt[21]]
(x+1)^3 - x^3 = 7{ (x^2+x)^3 }/88 {3(x^2+x) +1} -7 (x^2+x)^3 = 07t^3 -24t- 8 = 0 where t = x^2+x7t^3 -28t +4t-8 = 07t (t+2)((t-2) +4 (t-2) = 0(t-2) (7t^2+14t+4) =0now use x^2+x= t
It’s in my head.
Nice video
1/(x^3)-1/(x+1)^3=7/8 x=-2 x=1 x=(-1/2)±(1/14)iSqrt[147±28Sqrt[21] ]=-0.5±0.1(0.714285 recurring)iSqrt[147±28Sqrt[21]]
(x+1)^3 - x^3 = 7{ (x^2+x)^3 }/8
8 {3(x^2+x) +1} -7 (x^2+x)^3 = 0
7t^3 -24t- 8 = 0 where t = x^2+x
7t^3 -28t +4t-8 = 0
7t (t+2)((t-2) +4 (t-2) = 0
(t-2) (7t^2+14t+4) =0
now use x^2+x= t