Quadratic Functions: What the Discrimant tells you

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[@benmuirhead4229]

I’m 12 and your videos on quadratics are SO HELPFULL

[@irs4486]

common W

[@platypus4427]

How's being 15

[@JoshuaLokz]

Why is triangle used for discriminant I thought the triangle means change

[@musicbysasha_]

the triangle is the Greek letter delta which stands for 'd' or 'discriminant'

[@SplendidKunoichi]

it's the "change" to x away from the axis of symmetry x = -b/2a you would have to make in order to reach either side of the parabola.

[@orangecaprinun]

what does he mean by roots? intercepts?

[@tebogo743]

Yes, x-intercepts to be specific. The x-intercepts of a function are the points where the graph of the function crosses the x-axis. However, that is not the full story, roots of a function or an equation are values of x for which the function equals zero, this is what I mean, here is a function, f(x)=x²-1. Now lets make the function zero, we now have x²-1=0, let's solve this equation for x( solving also means finding the solution(s) to the equation),I am assuming you know factorization, (x-1)(x+1)=0, so then there is two solutions, x=-1 or x=1. You can test it yourself, if you make x=1 or x=-1 and put it in the equation x²-1, you will get 0, so indeed, -1 and 1 are the solutions to the equation. Now if you were to draw this function, you will see that at x=-1 and x=1 the graph crosses the x axis. So lets recap, roots are x-intercepts of the function, but roots are also the solutions to the equation f(x)=0, in the example above f(x) is x²-1, so while roots and x-intercepts refer to the same numerical values (that is., they are both the solutions to the equation 𝑓(x)=0, "roots" emphasizes the solution to the equation, and "x-intercepts" refers more to the graphical representation where these solutions cause the graph to intersect the x-axis. I know its a lot to take in, but I hope it helps. After reading all this, watch this video again, to see if it makes more sense.

[@gretawilliams8799]

The girl who shouted imaginary, She's in many videos

[@phenomenalphysics3548]

And I think she's a genius!!!😍

[@pola_behr]

@@phenomenalphysics3548 are you simping over a disembodied voice?

[@Steve.M]

I don’t think she’s real.

[@blue.haneul]

she's 'unreal'@@Steve.M

[@MathSciMadeSimple]

Thank you soooooo much!

[@phenomenalphysics3548]

4:41 TELL ME THE REASON WHY!!!!

[@zeroamu8250]

If the discriminant is lesser than 0 then it has to be a negative number and the sqrt of a negative number is always a multiple of 'i' [ i=sqrt (-1) ] and i is not a real number. Hence If the discriminant is lesser than 0 then the root is a non-real root.

[@AndrewTota]

Im writing this comment a day before it be exactly uploaded for 8 years