Resposta :
x/(x+1) + x + 1/x = 5/2
[x^2 + x(x + 1)(x) + (x + 1)] / (x + 1)(x) = 5 / 2
[x^2 +(x^2 + x)(x) + (x + 1)] = (5 / 2) ((x + 1)(x)
x^2 + x^3 + x^2 + x + 1 = (5 / 2)(x^2 + x)
2(x^3 + 2x^2 + x + 1) = 5(x^2 + x)
2x^3 + 4x^2 + 2x + 2 = 5x^2 + 5x
2x^3 + 4x^2 - 5x^2 + 2x - 5x + 2 = 0
2x^3 - 5x^2 - 3x + 2 = 0
equaaçaão do 3o grau.
Resolvendo:
x1 = 2,898
x2 = - 0,819
x3 = 0,421
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