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You are not logged in. #2 20060114 15:18:43
Re: calculus, volumey = ln x Draw a graph and note are going to integrate from y = 0 to y = 1. because of pi r^2 for area. (disk method, might be called) From an integral table: Great answer, but I wish I knew how to do the integral without the table lookup. Last edited by John E. Franklin (20060114 15:33:02) igloo myrtilles fourmis #3 20060114 15:36:10
Re: calculus, volumebut what happens with the y = 1? i need it to find the limits. it can't be the upper limit because the graphs don't intersect there. they intersect when x = e in this equation: y = ln x, so the upper limit should be e. correct me if i am wrong and please tell me why i am wrong. Last edited by hristo (20060114 15:43:47) #4 20060114 15:50:01
Re: calculus, volumeClick on graph to make bigger. igloo myrtilles fourmis #5 20060114 15:51:12
Re: calculus, volumeI am integrating along the yaxis, not the xaxis. igloo myrtilles fourmis #6 20060114 15:54:22
Re: calculus, volumeFor each microscopic y position, imagine a thin disc igloo myrtilles fourmis #8 20060114 16:00:42
Re: calculus, volumeNo problem. This is all fairly new to me, but hopefully someone can igloo myrtilles fourmis #9 20060114 22:47:56
Re: calculus, volumeThat's just integration by recognition. We know that if you differentiated , you'd get . So, if we want the answer to be half of that, we need to half the thing we're differentiating. Using this backwards shows that . Why did the vector cross the road? It wanted to be normal. #10 20060115 02:31:40
Re: calculus, volumeV = ∫2πx(f(x)g(x))dx Last edited by irspow (20060115 02:32:36) 