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Inequalities and descriminant- c1

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Reply 20
Original post by Zacken
Sorry! At least now you know. :biggrin:


Would've been nice to know for the exams I sat last year :rofl:

Thanks anyway
Reply 21
Original post by Andy98
Would've been nice to know for the exams I sat last year :rofl:

Thanks anyway


:colondollar: You must've done well anyway! :tongue:

No problem. :smile:
Reply 22
Original post by Zacken
If x=1x=1 then you end up with a division by 0.


Sorry to bring this up again, but what do you mean if X is less than/equal to 1 it will end in a division by 0? I don't get why you would be dividiving by 0.
Reply 23
Original post by Questioness
Sorry to bring this up again, but what do you mean if X is less than/equal to 1 it will end in a division by 0? I don't get why you would be dividiving by 0.


You are right in stating that x≤1x \leq 1, buuut we can't have x=1x=1 since if that was allowed then we'd be doing x−4x−1=1−41−1=−30\frac{x-4}{x-1} = \frac{1-4}{1-1} = \frac{-3}{0} but we can'd divide by 0 0\, so our inequality should be

x≤1x \leq 1 AND x≠1x \neq 1. But we can just simplify that as x<1x < 1.
Reply 24
Original post by Zacken
:colondollar: You must've done well anyway! :tongue:

No problem. :smile:


Well, I'm resitting C1&4 and S1 :tongue:

Original post by Questioness
Sorry to bring this up again, but what do you mean if X is less than/equal to 1 it will end in a division by 0? I don't get why you would be dividiving by 0.


x−4x−1\frac{x-4}{x-1}, when you use 1 it becomes 1−41−1=−30\frac{1-4}{1-1}=\frac{-3}{0} which is bad :yep:
Reply 25
Original post by Zacken
You are right in stating that x≤1x \leq 1, buuut we can't have x=1x=1 since if that was allowed then we'd be doing x−4x−1=1−41−1=−30\frac{x-4}{x-1} = \frac{1-4}{1-1} = \frac{-3}{0} but we can'd divide by 0 0\, so our inequality should be

x≤1x \leq 1 AND x≠1x \neq 1. But we can just simplify that as x<1x < 1.

Ok, makes sense. Thanks again :smile:.
Reply 26
Original post by Andy98
Well, I'm resitting C1&4 and S1 :tongue:


Good luck! The maths forum is here if you've got any queries. :biggrin:

x−4x−1\frac{x-4}{x-1}, when you use 1 it becomes 1−41−1=−30\frac{1-4}{1-1}=\frac{-3}{0} which is bad :yep:


Slowcoach. :wink:
Reply 27
You Get a rep Anyways. Sorry Zacken, I've already repped you :tongue:
Reply 28
Original post by Questioness
You Get a rep Anyways. Sorry Zacken, I've already repped you :tongue:


Don't worry about it! :smile:
Reply 29
I'm not done :colondollar:. Why is it that X can be equal to 4? That would also make 0 :s-smilie:. Not likin' the double standards here.
Reply 30
Original post by Questioness
I'm not done :colondollar:. Why is it that X can be equal to 4? That would also make 0 :s-smilie:. Not likin' the double standards here.


It's not a strict inequality, so x−4x−1=4−44−1=0≤0\frac{x-4}{x-1} = \frac{4-4}{4-1} = 0 \leq 0 which is true. 0 is less than or equal to 0.

You can do this on your calculator, it's all perfectly legit. But try dividing by 0 on your calculator, what happens?

Moral of the story: 0 in the numerator is okay. 0 in the denominator is bad news.
(edited 7 years ago)
Reply 31
Original post by Zacken
It's not a strict inequality, so x−4x−1=4−44−1=0≤0\frac{x-4}{x-1} = \frac{4-4}{4-1} = 0 \leq 0 which is true. 0 is less than or equal to 0.

You can do this on your calculator, it's all perfectly legit. But try dividing by 0 on your calculator, what happens?


Right- an error. Okay I get it.Thanks.
Reply 32
Original post by Questioness
Right- an error. Okay I get it.Thanks.


No problem!
Reply 33
Original post by Zacken
Good luck! The maths forum is here if you've got any queries. :biggrin:



Slowcoach. :wink:


I'm not one to spam :wink:


Ssshhh, I am also doing actual work :tongue:
Reply 34
Original post by Andy98
I'm not one to spam :wink:


Ssshhh, I am also doing actual work :tongue:


I'm doing actual work too. :colonhash:
Reply 35
Original post by Zacken
I'm doing actual work too. :colonhash:


Sure :rolleyes: :tongue:

What work? :eyeball:
Reply 36
Original post by Andy98
Sure :rolleyes: :tongue:

What work? :eyeball:


Uhm... uhm... okay nevermind. :tongue:
Reply 37
Original post by Zacken
Uhm... uhm... okay nevermind. :tongue:


Thought as much :rofl:
Reply 38
Original post by Andy98
Thought as much :rofl:


:talkhand:

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