Rationalizing Complex Denominators for Scientists

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Homework Statement



1/((i-s)^2)) how do i rationalize this , would i multpiy top and bottom by
(i+s)^2
 
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cragar said:
1/((i-s)^2)) how do i rationalize this , would i multpiy top and bottom by
(i+s)^2

(rationalize? anyway …)

Yup! :biggrin:
 
tiny-tim said:
(rationalize? anyway …)


By the way, what is the proper term? (assuming "rationalize" is not)
 
"Rationalize" is the correct vocabulary for what you wanted.
 


Unit said:
By the way, what is the proper term? (assuming "rationalize" is not)

Hi Unit! Hi symbolipoint! :smile:

Well, "rationalize" means to make rational, which this doesn't, neither in the English nor in the mathematical sense.

It actually puts a complex number into the standard x + iy form, so I'd prefer to say "put into standard form" …

however … now you raise the point, I see that http://hyperphysics.phy-astr.gsu.edu/hbase/cmplx2.html#c2 and others do say "rationalize" … I wonder why? :redface:
 
But it's asking to rationalize the denominator which is achieved. The denominator becomes real, and possibly rational depending on the value of s.
 
For ex. 1/i where i is complex number. By multiplying with i / i you get i / i2 = i / (-1), which makes the denominator real number (also rational) since I can write (-1) as (-1)/1 and the final equation would be i / (-1) / 1. Now the denominator is rational and I rationalize the equation. :smile:

Regards.