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One of the roots of (x^2 + 1)/x + x/(x^2 + 1) = 29/10 is (1 + sqrt(k))/5, where k is a negative integer.  Find k.

 Dec 6, 2019
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x2+1x+xx2+1=2910Let u=xx2+1.u+1u=291010u2+1029u=0(2u5)(5u2)=0u=52 or u=25xx2+1(1)=52 or xx2+1(2)=25Consider equation (1),5x2+5=2x5x22x+5=0x=2±224(5)22(5)x=1±245Consider equation (2),2x2+2=5x2x25x+2=0(2x1)(x2)=0All roots are purely real.The required integer is 24.

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 Dec 6, 2019

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