Question 373663
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Hi,
x^4-8x^2-20=0
(x^2 -10)(x^2 +2)= 0
(x^2 -10)=0
x^2 = 10
x = +-{{{sqrt(10)}}}
(x^2 +2 )= 0
x^2 = -2
x = +-{{{sqrt(-2)}}}
x = +-i{{{sqrt(2)}}}