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joel joel is offline
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Default complex numbers with excel

y= (-b+/-sqrt(b^2-4ac))/2a

y=(5+/-sqrt(5^2-4(1000))/2

y=2.5+31.52i
and
y=2.5-31.52i


the angle in radians is
atan(31.42/2.5)

convert radians to angles mult by 180/pi = 85.46

the length = sqrt((31.42^2)+(2.5^2)) = 31.62


follow same steps for 2nd root.


"Andrew" wrote:

Hello,
I am trying to find the complex roots of a polynomial using Excel. If
I have the polynomial s^2-5s+1000, I should get the roots to be 31.6
angle 85.4 and 31.6 angle -85.4. How do I do this calculation in
excel?

thanks