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Question

Find the multiplicity root of the equation
f(x) = x4 + x3 – 6x = 14.

f(x) = x^4 + x^3 - 6x = 14

Answer 1

x4 + x3 – 6x - 14 = 0.
(x^2 - 0.329648003x - 3.528912291)
(x^2 + 1.329648003x + 3.967228099) = 0
(x + 1.72093294)(x - 2.050580943)
(-1.329648003 +/- sqrt(2.2458266848256 -15.868912396))/2
x = - 0.664824 +/- sqrt(-3.405771427936
x = - 0.664824 + i1.84547322
x = - 0.664824 - i1.84547322
x = - 1.72093294
x = + 2.050580943

Answer 2

two = signs in one equation is invalid = < > + - are all one side against the other. when all else fails divide all by x