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**Hannibal lecter****Member**- Registered: 2016-02-11
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Hi,

How to right imaginary number with inequalities and in interval notation like this :

x^2 ≥ -1

it is either x ≥ + √-1

or x ≥ - √-1

so how to right it in number Line? and in interval notation,

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The complex numbers don't form an ordered field. Think about it: what does it mean to say that ? The only way we can compare 'sizes' of complex numbers is to take the modulus. The most you can say is that .If is a real number, then , always. In fact, that's sometimes given as the definition of a real number.

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**Hannibal lecter****Member**- Registered: 2016-02-11
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but I got this while I was trying to solve an inequality :

it make me feel confused with this x^2 + 1

I don't know how to end my solution

*Last edited by Hannibal lecter (2016-12-24 05:52:23)*

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You can just multiply both sides by (since it is always positive) to get Do you see where to go from here?

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**Hannibal lecter****Member**- Registered: 2016-02-11
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yes, the interval will be (-∞,-1] U [1,∞) right?

*Last edited by Hannibal lecter (2016-12-24 09:31:21)*

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Yes.

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

That is what I am getting.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Hannibal lecter****Member**- Registered: 2016-02-11
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now I'm good with absolute value hehehe but I'm not genius, I need to be genius in the future

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

I knew a kid who everyone told him he was a genius. Pretty soon, his head got so big he could not squeeze it through his own front door. A few nights outside in the cold brought him back to reality and his head shrunk to normal size. He became a hard worker and forgot that genius stuff. He does not do much better than when he believed he was a god but he at least can get home and go through the door. The moral of this story? I have no idea.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Hannibal lecter****Member**- Registered: 2016-02-11
- Posts: 224
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thank you

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