How to solve a polynomial inequality?

Find the set of values of x for which 1/(x^2 + 2x - 3) is less than 0. #math #maths #mathematics

Adapted from

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[Goose____]

i feel like you're giving us easy questions to boost our confidence lol

[paulfoss]

People often complain when mathematicians refer to opaque statements as obvious or trivial or when simple problems are referred to by math educators as tricky, but really nothing in math is innately obvious or tricky, it all depends on prior knowledge and skill. We shouldn't think about terms like "easy" and "hard" as properties of the problems themselves, but rather indications of the target audience. I don't feel I am the target audience for this, but I still like these kinds of problems because I think its good to maintain foundations and they don't take much time.

[PhoenixFires]

This is bringing back all my high school calculus. I threw it all out but its crawlings its way out of my brain's recycle bin.

[viber]

its important to note that even if the inequality was less than or equal to 0, those points would still be omitted as they would create a division by zero.

[krishgarg]

Our teacher taught us inequalities in a way that, if you can find all the real zeroes of a function (it can have exponential, modulus, and polynomials of any degree given factorized so it is possible to find zeroes), it will solve for the sign scheme of the function for any interval. And we don't have to put a single value in the function except infinity to get the signs of different intervals lol.

[MattKyleBullerthemattkylefiles]

always test a value from each range in the original inequality or equation

[digvijaykale]

I love maths and your video is amazing 👍

[alosoraah]

Thank you
Bruh why there is no teacher that taught me
Draw the function between the points
Some just said “plus, minus, plus” and i had no idea why

[ANASzGAMEOVER]

This is literally what we're taking in school this year, seriously, this education system needs a boost

[dannyluo]

I solved this by myself, and I find it easy.

[yourdadpayrespect]

Basic mathematics jee, this was my first illustration

[brianblessednn]

People in the comments are like "This problem that was chosen to be solvable in under a minute isn't difficult"

[scrpr]

Hi, I havent passed this type of excercises yet, so can anyone tell me how we went from:
1/x²+2x-3 > 0
to simply
x²+2x-3 > 0
please?

[godlshinigami]

Brother this was not tricky. This question can be done by any class 11 student who has taken maths

[John-lfxf]

This is trivial. It is just the values for where the decimation is less than zero. Which is just the zeroes of the quadratic a, b. Either from infinite to those or those to each other depending on how the quadratic opens.

[soundest]

Tricky if you’re not through precalculus yet, sure! But that’s okay, because anyone at every level of mathematics should be able to be challenged and enjoy the subject.

[fackingcopyrights]

by the time you explaied it i tested every whole number between 1 and -3

[neilmorrone]

Yes, this is a bit of a 'thinker, ' especially if isn't thinking well! Thank you! It was fun to utilize one's logical mind and approach, rather than "just" algebra!

[predrik]

-3<x<1 after hearing just hearing the first step aaaa

[quetzalcoatlustheflyinggir]

I think what catches most people up is when it asks for set notation.
In this case, that is literally just:
x = {-3 < x < 1}
I think.