# word problem for "complex roots"

Discussion in 'Secondary Education' started by edu, Nov 1, 2012.

1. ### eduRookie

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Nov 1, 2012

Dear pals,
Can anyone help give a real world problem that yeilds an equation (or of type) x^2+1=0 (should give complex roots )
thanks.

3. ### MathemagicianGroupie

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Nov 1, 2012

Try p 32 or 59 here:

http://glencoe.mcgraw-hill.com/sites/dl/free/007873830x/518871/a2wpp.pdf

They are all highly contrived. In most cases the imaginary solutions would be extraneous unless the kids were working with currents (which I doubt). I wouldn't use word problems with complex roots. I would just say they may see it later in physics or higher maths. They can do plenty of word problems with quadratics and real roots...just my 2 cents...not everything needs to have an instant real-world application.
I always tell my alg kids that sometimes they need to appreciate an idea even if it isn't immediately applicable. They seem ok with that level of honesty.

4. ### AliceaccMultitudinous

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Nov 2, 2012

Imaginary numbers simply don't come up a whole lot in the real world, so they're all going to be fairly contrived.

That's OK; the older kids taking Algebra II should be able to get past the idea of "When does my mother ever use this?"

5. ### eduRookie

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Nov 2, 2012

Thank you. I taught complex numbers in Alg-2 class today. I slightly introduced the concept of electromagnetic field strength which is a complex sum of electric field strength and magnetic field strength

electromagnetic field strength = electric field strength+i*magnetic field strength.

Students are convinced. But I would have been more happy if I could give them a real example.

--Cheers.

6. ### Expo MarkersRookie

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Nov 3, 2012

Electrical engineers use imaginary numbers to find current and physicists use them for quantum mechanics.

But the former requires Calculus. Sorry!