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El_Arrow
 one year ago
need help in finding the length of the curve
El_Arrow
 one year ago
need help in finding the length of the curve

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El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0y = 2ln(sin(x/2) pi/3<x<pi

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0i got it down to the integral of csc(x/2)

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0@freckles @Vocaloid @amistre64 @zepdrix

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3can you show your working to get to that point?

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0yeah i'll try to draw it out

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0dw:1443753630087:dw

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3sin^2 + cos^2 = 1 1 + cos^2/sin^2 = csc^2 ok, im on the same page as you now

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0yeah thats what i did for the derivative

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3an old trick is to multiply by (csc + cot) i beleive

zepdrix
 one year ago
Best ResponseYou've already chosen the best response.0Oh cosecant integral :) This is one of those annoying ones. Do you remember secant integral? it's very similar process for this one

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0yeah i got the integral for cosecant its lncscx+cotx

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3csc + cot derives to (csc^2 + csc cot)

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3the x/2 pops out tho so we need to adjust by a constant right?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3ln(cscu + cotu) (csc^2u + cscu cotu) u'  csc u + cot u u = x/2; u' = 1/2

amistre64
 one year ago
Best ResponseYou've already chosen the best response.32 ln ... seems fair to me

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0wait how did you get csc^2u + cscu cotu?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3what is the derivative of csc u + cot u ?

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0oh but shouldnt it be negative

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0why are we taking the derivative of those two if we already got the integral?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3dw:1443754334011:dw

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3what is your question then?

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0my question is why is my answer different from that of wolframalpha i got 2ln12sqrt(3)

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0and they got 2ln2sqrt(3)?

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0i dont know if there is a step you gotta do before plugging in the integration numbers or what?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3\[2ln(csc(pi/2)+cot(pi/2)+2ln(csc(pi/6)+cot(pi/6))\] \[2[ln(csc(pi/2)+cot(pi/2)+ln(csc(pi/6)+cot(pi/6))\] \[2ln(\frac{csc(pi/6)+cot(pi/6)}{csc(pi/2)+cot(pi/2)})\]

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0okay so csc(pi/6) is 2 and cot(pi/6) is sqrt(3)

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0and csc(pi/2) is 1 and cot(pi/2) is 0

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0so dw:1443755083983:dw

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0but dont you do that only when your substracting?

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0when do you divide the numbers when there is a natural log i mean?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.32 ln2sqrt(3) 2 ln1/(2sqrt(3)) 2 ln(2+sqrt(3))/(43)

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3log(a)  log(b) = log(a/b) for all logs

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0but your adding them?

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3no, 2ln(b) 2ln(a) = 2ln(a)2ln(b)

freckles
 one year ago
Best ResponseYou've already chosen the best response.0hey where you guys at... have you guys gotten to \[2 \int\limits_\frac{\pi}{6}^\frac{\pi}{2} \csc(u) du\] if this looks funny I just subbed x/2 for u

El_Arrow
 one year ago
Best ResponseYou've already chosen the best response.0i think you have the b on top of the a

amistre64
 one year ago
Best ResponseYou've already chosen the best response.3i was trapped in OS purgatory ...
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