Question 260990
 t^5-256t=0
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t*(t^4 - 256) = 0
t = 0
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(t^2 - 16)*(t^2 + 16) = 0
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t^2 - 16 = 0
t = +4
t = -4
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t^2 + 16 = 0
t = +4i
t = -4i