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integration help (1 Viewer)

100percent

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how do you integrate
2x - 3
-------------- dx
x² - 2x + 2

with boundaries 2 & 1. thanks.

btw question is from cambridge page 155 question 17
 

shafqat

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100percent said:
how do you integrate
2x - 3
-------------- dx
x² - 2x + 2

with boundaries 2 & 1. thanks.

btw question is from cambridge page 155 question 17
= 2x-2 / x² - 2x + 2 - 1/x² - 2x + 2
= 2x-2 / x² - 2x + 2 - 1/(x-1)^2 + 1
= log (x² - 2x + 2) - tan^-1(x-1)

edit: from 1 to 2, ah couldnt be bothered, i think you can do it yourself
 

100percent

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it never occured to me to split the 2x - 3 to 2x - 2 -1.
thanks man
 

..:''ooo

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100percent i think u need a treatment of corroneous integration questions
 

KFunk

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I've been doing that coroneous revision set of 100 questions. It's a hell of a lot of integration.
 
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uh from memory, I think u can change the (2^x)^1/2 to 2^(x/2) and then change the 2 to a e^ln2.
So u now have integral of e^((0.5x)ln2)dx which with a bit of trickery you can do.
Could be wrong but I think that's how you do it.
 

KFunk

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I think that's pretty much it.

&int; 2<sup>x/2</sup> dx

convert it to base e to make your life less difficult ---->
e<sup>u</sup> = 2
log<sub>e</sub>2=u
hence 2 = e<sup>ln2</sup>

&int; 2<sup>x/2</sup> dx
= &int; (e<sup>ln2</sup>)<sup>x/2</sup> dx
= &int; e<sup>(x.ln2)/2</sup> dx
= (2/ln2) &int; ln2/2.e<sup>(x.ln2)/2</sup> dx
= (2/ln2).e<sup>(x.ln2)/2</sup> + C
= (2/ln2)&radic;(2<sup>x</sup>) + C
 

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