#could someone help me with this integral?

93 messages · Page 1 of 1 (latest)

abstract tapir
ashen ventureBOT
stone atlas
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could always use partial fractions if ur bothered

thick wagon
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Partial fraction won’t tly work fr

stone atlas
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the other option is to complete the square

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it seems

thick wagon
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Cause they are both the same thing

stone atlas
thick wagon
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But the denominator is the same

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A/(x^2+x+1)+b/(x^2+x+1)

stone atlas
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oh wait

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i forgot

thick wagon
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When multiplying the two sides

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Yeah

stone atlas
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partial fractions

thick wagon
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Yeah it doesn’t work sadly

stone atlas
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whoops, i was being silly

thick wagon
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I’m being a bit more silly

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So, how would one use complete the square

stone atlas
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i forgot 1/(A+B) cant be turned into 1/C +1/D

thick wagon
stone atlas
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after a usub

thick wagon
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Ah

stone atlas
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very pretty

thick wagon
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The arc tan pray thing

stone atlas
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yes xd

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but our friend seems to be asleep

thick wagon
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Bruh the solution is fucking devious

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1 can be rewritten as a sun

stone atlas
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1?

thick wagon
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$\int \frac{dx}{x^2+x +1}$

bold ridgeBOT
thick wagon
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3/4 and 1/4

stone atlas
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yes xd

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its a classic

thick wagon
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(X+1/2)^2

stone atlas
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my favourite completing the square ahhaha

thick wagon
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Wait

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Yeah

stone atlas
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u need to take out all the fractions

thick wagon
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$\int \frac{dx}{((x+\frac{1}{2})^2 \frac{3}{4}}$

stone atlas
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take out a factor of half from the bracket -> 1/4 -? 16 outside

bold ridgeBOT
thick wagon
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My latex ass gimme a few

stone atlas
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its okay i cant latex at all xd

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also i think i will slepe

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goood luck to tasakman95

steel crown
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cant you just calculate int(1/(x²+x+a))dx and then do leibniz rule?

stone atlas
steel crown
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wellll

stone atlas
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seems a bit overkill

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i think working with trig is easier

stone atlas
steel crown
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d/da

stone atlas
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but why would that make it easier

steel crown
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because this int(1/(x²+x+a))dx isnt that hard

stone atlas
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but its fundamentally the same as the other

thick wagon
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The answer is no ; )

steel crown
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wdym?

thick wagon
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An integral is not a limit

steel crown
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ik

vernal crane
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$\int \frac{d!x}{((x+\frac{1}{2})^2+\frac{3}{4}}$

There was meant to be a plus

bold ridgeBOT
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∫(∂∑)ω=∫(∑)dω

vernal crane
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You can just do $x+\frac{1}{2}$=$\frac{\sqrt{3}}{2}\cos(u)$

bold ridgeBOT
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∫(∂∑)ω=∫(∑)dω

vernal crane
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oh wait not cos

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whatever

thick wagon
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It’s arc tan I thought

vernal crane
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oh wait i am tripping

abstract tapir
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(sry for my english im from poland)

vernal crane
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So $x+\frac{1}{2}=\frac{\sqrt{3}}{2}\tan(u)$ and $d!x=\frac{\sqrt{3}}{2}\sec^2ud!u$.

And then it becomes $\frac{8\sqrt{3}}{9}\int\frac{\sec^2ud!u}{\sec^4u}$
hopefully

bold ridgeBOT
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∫(∂∑)ω=∫(∑)dω

vernal crane
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and $\int\cos^2(u)d!u$

bold ridgeBOT
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∫(∂∑)ω=∫(∑)dω

steel crown
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dont you just do u= x+ 1/2 and du=dx to make it int(1/(u²+((sqrt(3))/2))dx to then use int(1/(x²+a²)dx=1/a arctan(x/a) ?

vernal crane
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ok so like

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somehow i didnt realize there was an extra squared

vernal crane
steel crown
obsidian raptor
vernal crane
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ye

obsidian raptor
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This is your answer

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If your asked the question