Question 495037
{{{x^4 = 16}}}
{{{x^4 - 16 = 0}}}
{{{(x^2-4)*(x^2+4) = 0}}}
{{{x^2-4 = 0}}}
x = -2, +2
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{{{x^2+4 = 0}}}
{{{x^2 = -4}}}
x = -2i, +2i
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The number of roots = the order of the equation.
4th order --> 4 roots
Sometimes the roots are repeated, eg, x^3=0
--> x = 0,0,0
3 roots, of 0, multiplicity 3