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Integration question (1 Viewer)

tOnnyAyye

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Hey. I need a solution for this question.

a) Draw a neat sketch showing the area bounded by the curve y= 1 + sqrt(x) and the x-axis 0<x<4 (note that < is "less than or equal to" for this question)

b) Find the solid formed when the area is rotated about the y-axis

I know part a but not part b. the answer for part b is 208pi/5 units^2.
 

apollo1

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you want to find:

volume of the area between y = 1 + sqrt(x) and the x-axis between x = 0 and x = 4

 

MrBrightside

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you want to find:

volume of the area between y = 1 + sqrt(x) and the x-axis between x = 0 and x = 4

I think a diagram would better explain this. btw where did the 4 come from?
 

SpiralFlex

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I think Apollo cleverly worked backwards. Either that or he has found the exact same question in a textbook.
 

apollo1

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I think Apollo cleverly worked backwards. Either that or he has found the exact same question in a textbook.
i just used my advanced 4U knowledge of volumes to get that. I still used 2U methods though.
this is wat i did:
((Volume of rotating x = 4)-(volume of rotating x = (y-1)^2)) (between y =1 and y = 3) + (volume of rotation of x = 4 between y = 0 and y = 1)
 

hscishard

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Spiralflex is pointing out that the question didn't give the bounds and that you found the bounds with the given answer and hence was able to post the solution OR you've done it before
 

apollo1

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Spiralflex is pointing out that the question didn't give the bounds and that you found the bounds with the given answer and hence was able to post the solution OR you've done it before
well he did give bounds. (i saw 0<4 and i presumed he meant 0 to x to 4) and i do 4 unit so i culdnt hav seen this question previously.
 
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SpiralFlex

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well he did give bounds. (i saw 0<4 and i presumed he meant 0 to x to 4) and i do 4 unit so i culdnt hav seen this question previously.
I can't see where he said that? Did he delete it?
 

apollo1

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Hey. I need a solution for this question.

a) Draw a neat sketch showing the area bounded by the curve y= 1 + sqrt(x) and the x-axis 0<x<4 (note that < is "less than or equal to" for this question)

b) Find the solid formed when the area is rotated about the y-axis

I know part a but not part b. the answer for part b is 208pi/5 units^2.
.
 

Drongoski

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I recall indicating (& later deleting) "info missing" as the 1st response to the post; I could not see any limits.
 

apollo1

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also ull notice that if you quote the Original post, you can actually see the limits written out properly.
 

SpiralFlex

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Uh guys. Is it me or is our information in our LHS boxes bolded?
 

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