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Equation of Tangent (1 Viewer)

Smile12345

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Yeah ok, I see what you mean Epikhigh... :) what was it like for you?
 

EpikHigh

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Hmmm. I'm not getting it... a=6 b=24 c=4

-24+- square root 24^2 -4x 6 x 4 (all over)
12

I'm just not getting -6+-root 30 / 3

Thanks for your help. :)
are you sure the asnwer is -6? I'm getting -2 +- root 30 /3

Basically you have to simplify the surd, you have your answer -24 +- the sq root of 480 all over 12 right? 480 = sqroot(16x30) = 4root30 and from that you get -2 +- (root30)/3
 

Smile12345

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are you sure the asnwer is -6? I'm getting -2 +- root 30 /3

Basically you have to simplify the surd, you have your answer -24 +- the sq root of 480 all over 12 right? 480 = sqroot(16x30) = 4root30 and from that you get -2 +- (root30)/3
I reckon the answer is wrong... Yes, ok... I do have that answer... Then just got to do the next part.

Cheers, I follow you and got -2+- (root 30)/3... Thanks. I hate it when the answers are wrong. :)
 
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Smile12345

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For my rank in Mathematics...

Say Term 1 - 15% and Term 2 - 30%...

How do I work out my average mark (Which would be what made my ranking)?? (I can't just add them and divide by two as if they were the same weighting.)

Thanks in advance. :)
 

EpikHigh

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For my rank in Mathematics...

Say Term 1 - 15% and Term 2 - 30%...

How do I work out my average mark (Which would be what made my ranking)?? (I can't just add them and divide by two as if they were the same weighting.)

Thanks in advance. :)
Turn your mark into percentages, then multiply your percentages with their respected weightings and add em together.
 

Smile12345

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Turn your mark into percentages, then multiply your percentages with their respected weightings and add em together.
Thanks... :) I have Term 1 and Term 2's as percentages... Yeah ok.... So I'd have a mark out of 45 (as I've done 45% weighting so far) x 100 to get a percentage?
 

EpikHigh

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This is a dumb statement but... The 1/2 Yearlies and Yearly (in my case) are weighted more because they assess more outcomes.... This correct?
Depends on the school mang, you've seem to have 45% already assessed? so have 55% left so it might be split up into 30% and 25% if you have only 2 assessments left. depends though.
 

Smile12345

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Depends on the school mang, you've seem to have 45% already assessed? so have 55% left so it might be split up into 30% and 25% if you have only 2 assessments left. depends though.
Sorry, it really was a stupid thing to say!! Yup, that's correct...15% and 40%... :)
 

Smile12345

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Could someone please help me to the following? (Using quotient rule)... x^3 / x^2-4

I am getting -24/(x^2-4)^2

I am doing something wrong I know... :)

Thanks for your help in advance. It is greatly appreciated.
 
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EpikHigh

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Could someone please help me to the following? (Using quotient rule)... x^3 / x^2-4

I am getting -24/(x^2-4)^2

I am doing something wrong I know... :)

Thanks for your help in advance. It is greatly appreciated.
Best way to do quotient rule questions at first is to identify v and u so set it out like this

f(x) = x^3/x^2-4

u = x^3 v = x^2-4
u' = 3x^2 v' = 2x

vu' - uv' all over v^2

2x(x^2-4) - 2x^4 all over (x^2-4)^2

and then expand and simplify.
 

Smile12345

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Best way to do quotient rule questions at first is to identify v and u so set it out like this

f(x) = x^3/x^2-4

u = x^3 v = x^2-4
u' = 3x^2 v' = 2x

vu' - uv' all over v^2

2x(x^2-4) - 2x^4 all over (x^2-4)^2

and then expand and simplify.
Thanks heaps.... :)
 

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