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Help with this math question!

The equation:

y = 3x^2 + (k-2)x + 3

Has two real roots.

Work out the values of k.

I'd be grateful if anyone could help me with this :smile:

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Original post by Federerr
The equation:

y = 3x^2 + (k-2)x + 3

Has two real roots.

Work out the values of k.

I'd be grateful if anyone could help me with this :smile:

Use b2−4acb^2 -4ac
where
a=3
b=k-2
c=3

the question tells us the equation has 2 real roots
∴b2−4ac>0\therefore b^2 -4ac > 0
(edited 7 years ago)
Original post by Federerr
The equation:

y = 3x^2 + (k-2)x + 3

Has two real roots.

Work out the values of k.

I'd be grateful if anyone could help me with this :smile:
use the discriminant and 2 real roots means that the equation must be greater than 0 solve from there :smile:
Reply 3
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Federerr
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19
Original post by hamza772000
use the discriminant and 2 real roots means that the equation must be greater than 0 solve from there :smile:


Well I know that haha.

I got an answer just wanna see if I got it right :tongue:

Do it hamza lemme know what yah get init.
Original post by Federerr
Well I know that haha.

I got an answer just wanna see if I got it right :tongue:

Do it hamza lemme know what yah get init.
lemme have a go then :smile:
Original post by Federerr
Well I know that haha.

I got an answer just wanna see if I got it right :tongue:

Do it hamza lemme know what yah get init.
I got K=8 and K=-4
Original post by Federerr
Well I know that haha.

I got an answer just wanna see if I got it right :tongue:

Do it hamza lemme know what yah get init.


k>8
k<-4
Reply 7
Avatar for Federerr
Federerr
OP
19
Original post by will'o'wisp
k>8
k<-4


That's what I got :tongue:
Original post by hamza772000
I got K=8 and K=-4


but it's an inequality you're solving.... you even said set the discriminant greater than 0...
Original post by Federerr
That's what I got :tongue:


Awesome i sometimes do dis and ask ppl to do the question for me and check if i got the right answer xD
Original post by Federerr
Well I know that haha.

I got an answer just wanna see if I got it right :tongue:

Do it hamza lemme know what yah get init.




Posted from TSR Mobile
1476301720207.jpg35.8KB
Reply 11
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Federerr
OP
19
Original post by will'o'wisp
Awesome i sometimes do dis and ask ppl to do the question for me and check if i got the right answer xD


Yehh! It's so frustrating when you can't find the solutions anywhere haha.
Original post by will'o'wisp
but it's an inequality you're solving.... you even said set the discriminant greater than 0...
Yeah, I realised, look at the attachment below
Reply 13
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Federerr
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19
Original post by hamza772000


Nice handwriting :tongue:
Original post by Federerr
Nice handwriting :tongue:
It was in a rush, r u taking the piss? lol :P
Reply 15
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Federerr
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Original post by hamza772000
It was in a rush, r u taking the piss? lol :P


Nah it's actually naaaaas
Original post by Federerr
Nah it's actually naaaaas
well, here it's nasty but ok :P
Reply 17
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Federerr
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19
Original post by hamza772000
well, here it's nasty but ok :P


I got handwriting like a yr 2 kid :tongue:
Reply 18
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Federerr
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19
woah sorry.

we ain't all as clever as u.

Spoiler

Original post by Federerr
I got handwriting like a yr 2 kid :tongue:
lol it dont matter haha :P

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