We just started these at school, but I have some questions..(adsbygoogle = window.adsbygoogle || []).push({});

Inequalities on number line (x) graphs..

Using x = 0 testpoint..

Let's say I have (x+2)(x-4) > 0, (0 + 2)(0 - 4) would be -8, and -8 !>0, so it would be a disjunction, right? But if it was positive and satisfied the inequality, it would be a conjunction, right?

OR what if it was < 0 instead, if it satisfied it would be a disjunction and if it didn't satisfy it would be a conjunction, right?

And let's say I have x(x-2)(x+4) > 0, the teacher taught us this method where we plot -4, 2 and 0 on a number line and place positive signs and negative signes over each one accordingly so that the satisfying inequality would be where the 3 signs ontop of each other would be + or -, according to the inequality...

IS there an easier way to do this?

I'm sorry that I don't make much sense, I'm in a hurry...

Hope someone can make sense of my words and help!

Thanks.

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# Polynomial Inequalities

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