Find the two real roots of the equation x^4 -5=4x^2 Give the roots in an exact form.
Disguised quadratic. Let y=x^2So quadratic become y^2-4y-5=0so (y-5)(y+1)=0so y=5 and y=-1so x^2 = 5 or -1cannot be -1 as not real henso x^2=5x=+-sqrt(5)
RJ
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