x4+x2+1=0怎么求解x,(式子里面是x的四次方和二次方)

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x4+x2+1=0怎么求解x,(式子里面是x的四次方和二次方)
x4+x2+1=0怎么求解x,(式子里面是x的四次方和二次方)

x4+x2+1=0怎么求解x,(式子里面是x的四次方和二次方)
0 = x^4 + x^2 + 1 = x^4 + 2x^2 + 1 - x^2 = (x^2 + 1)^2 - x^2
= (x^2 + 1 + x)(x^2 + 1 - x),
0 = x^2 + x + 1,Delta = 1 - 4 = -3.
x(1) = [-1 + (-3)^(1/2)]/2 = [-1 + i(3)^(1/2)]/2 或x(2) = [-1-(-3)^(1/2)]/2 = [-1-i(3)^(1/2)]/2.
0 = x^2 - x + 1,Delta = 1 - 4 = -3.
x(3) = [1 + (-3)^(1/2)]/2 = [1 + i(3)^(1/2)]/2 或x(4) = [1-(-3)^(1/2)]/2 = [1-i(3)^(1/2)]/2.
综合,有,
x(1) = [-1 + i(3)^(1/2)]/2
x(2) = [-1 - i(3)^(1/2)]/2.
x(3) = [1 + i(3)^(1/2)]/2
x(4) = [1 - i(3)^(1/2)]/2.

实数范围内无解我要的是虚根

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