Find the discriminant and the number of real roots for this equation. x2 + 2x + 8 = 0 A. 32; one real root B. –28; no real roots C. –28; one real root D. 32; two real roots
do you know the formula for discriminant ?
D = b^2 -4ac do you know the value of a,b and c ?
Isn't like b2-4ac
yes this is
A=1 b=2 c=8
yes this is correct
so just yous these value of a ,b and c and calculi the discriminant value
this is easy courage please
2^2-4(1)(8) 4-32 =28?
4-32 = ? not 28
It would be -28 ?
yes -28 so what is less than zero do you know the case when the discriminant is less than zero what roots has the quadratic ?
do you learned it ?
It's would be one real ?
Or because it's negative it would have no real
no there are 3 cases discriminant let D D > 0 there are two real ,different roots D = 0 there are two real equal roots D < 0 ?
I'm so confused
yes your last answer is right sure
so when the discriminant is less than zero so the quadratic have not real roots ok. ?
Okay
Or because it's negative it would have no real this your answer is right hope do you understand it now ok. ?
Yes I do Thank you !
welcome was my pleasure and anytime good luck bye bye
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