(Integration), what did I do wrong? (1 Viewer)

enigma_1

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From the first line to the second line you just separate the numbers in the numerator to make your life easier

x^3/x^2 - 2x^2/x^2 + 1/x^2

= x - 2 + 1/x^2

= x - 2 + x^-2

Just integrate that and it becomes

[ x^2/2 - 2x -1/x]

then plug in the 2 and the 1.

(2^2/2 - 2(2) - 1/2) - (1/2 - 2 - 1)

= 0

/thread
 

BlueGas

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Ok.. i'm just gonna say your factorisation is not correct. Look at Perve's/Sausages working and follow.
So now you say that my factorisation was not correct? You know you were the only actually who stirred this up? Because the whole time you were saying that my factorisation was not wrong.
 

Parvee

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My second line is basically where I factorise, can't you see that?
your second line was wrong though, that's why you aren't getting the correct answer

you should of ended with x-2+1/x^2

From the first line to the second line you just separate the numbers in the numerator to make your life easier

x^3/x^2 - 2x^2/x^2 + 1/x^2

= x - 2 + 1/x^2

= x - 2 + x^-2

Just integrate that

/thread

stronk post

even though two people posted the same thing 30mins ago
 
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BlueGas

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And I was apparently the troll...
 

Librah

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So now you say that my factorisation was not correct? You know you were the only actually who stirred this up? Because the whole time you were saying that my factorisation was not wrong.
i'm saying > x^3-2x^2= x^2(x-2) was correct, when i say your factorisation was correct. Not your entire line.
 

enigma_1

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your factorising was wrong though, that's why you aren't getting the correct answer

you should of ended with x-2+1/x^2




stronk post

even though two people posted the same thing 30mins ago
OP obv didn't get it initially
 

BlueGas

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i'm saying > x^3-2x^2= x^2(x-2) was correct, when i say your factorisation was correct. Not your entire line.
And now you're specifying what you meant by my factorisation? I already knew my factorisation was correct, but you're explanation was useless.
 

enigma_1

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And now you're specifying what you meant by my factorisation? I already knew my factorisation was correct, but you're explanation was useless.
ceebs reading through 49 posts but do you get it now?
 

BlueGas

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no, i just question the legitimacy of a poster when a question goes to 3 pages. apologies if i caused any offence
No offence taken, it was actually 3 pages of posts from a person who didn't explain what he was trying to say.
 

BlueGas

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It's not wrong, but i don't get why you would do it. It's just wasting an additional line of writing.
I said your factorisation was not wrong... But the thing you ended up with in the end was completely wrong.
Ok.. i'm just gonna say your factorisation is not correct. Look at Perve's/Sausages working and follow.
This is where you confused me big time, the whole time you were saying that my factorisation was not wrong, and then you finally say that it's not correct.

Can you repost what exactly confused you.
 

Librah

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This is where you confused me big time, the whole time you were saying that my factorisation was not wrong, and then you finally say that it's not correct.
"Ok.. i'm just gonna say your factorisation is not correct. " I said that for arguments sake, like "just assume this is wrong and move on" type thing.
 
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oh deary, the cancelling out of the denominator when both terms do not include it is an ultimately pet peeve for my maths teacher. Don't worry if you see your teacher spluttering in disbelief why some people do that, in front of the class, you would remember not to do that

x^2 (x-2) + 1 over x^2 you cannot cancel x^2 as there is a 1 that does not have x^2
 

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