Math problem rational inecuations

[gh0st]

2x    -    x     -       x-1     >= 0
----      -----         -------
x+1       x-1             x

meh I got a long polinomy I guess Im doing something wrong I guess too that I need to apply a tricky algebra factorization that I dont know some help here

[Deque]

Does that help you to go on with the rest?

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[ande]

You doing discrete mathematics?

[Deque]

If you mean me: I had some of it at university.

[ande]

Both of you for that matter I ad a full course of it last semester.

[gh0st]

for finding roots in:
-2x^2+x-1 we need to apply the cartesian plane? like I did before in my last post? gotta do a bit of reseach

[Deque]

The cartesian plane will help to get an imagination of the function and sometimes spares you even calculating roots if you see that there are none. But in general you would use a formula for quadratic equations to get a root of that.

In case of the denominator you can already see the results by looking at this:
x^3  - x
=(x+1)(x-1)x

You have two cases that make your inequation true:
1. denominator > 0 and numerator >= 0
2. denominator and numerator < 0

I ad a full course of it last semester.

I didn't have a full course, but several courses that did discrete mathematics like cryptography, probability calculus and statistics, numerical mathematics, algebra 1 and 2, algorithms and datastructures, and theoretical computer science.

[gh0st]

I did that problem I guess that imaginaries numbers are nerfed in the interval the inverval is only for real numbers

[Deque]

I did that problem I guess that imaginaries numbers are nerfed in the interval the inverval is only for real numbers

I don't understand you.

[kat]

Deque already solved the problem. You should plot the function and you see the answer is (-infinite,-1) and (0,1). The roots are not in the field of real numbers, but complex (-1+-isquare7)/-4. The poles are 0, 1 and -1. I ploted the function on my mobile phone for you:)

[gh0st]

@deque: I meant that the roots of -2x^2 +x -1 are irrational numbers* so they are not prevalent in the interval for finding them you hate to use the cuadratic formule http://en.wikipedia.org/wiki/Quadratic_equation#Quadratic_formula Im now solving problems about absolute value pretty interesting may post some of them as well