Recent content by delapcsoncruz

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    Integral calculus: volume of a solid of revolution

    ok i'll do that. you are right, 't' takes the place of either dx or dy, it is the thickness. thank you very much for your reply and time. appreciate it. thanks.. :))
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    Integral calculus: volume of a solid of revolution

    Homework Statement Find the volume of the first quadrant region bounded by x=y-y3, x=1 and y=1 that is revolved about the line x=1. The Attempt at a Solution dV=∏R2t where : t=dy R=1-(y-y3) =1-y+y3 so.. dV=∏(1-y+y3)2dy dV=∏(1-2y+y2+2y3-2y4+y6)dy V=∏∫ from 0 to 1 of...
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    Integral calculus: plane areas in polar coordinates

    can you give me an example of your useful tip.. please..
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    Integral calculus: plane areas in polar coordinates

    the value of 'r' in 5pi/4 is -1.41 , so that is also equal to pi/4 which r is 1.41
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    Integral calculus: plane areas in polar coordinates

    can you please give me of an example using your said useful tip.. please..
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    Integral calculus: plane areas in polar coordinates

    what is the area inside the graph of r=2sinθ and outside the graph of r=sinθ+cosθ? so i compute for the values of 'r',... but, i only got one intersection point which is (45°, 1.41). there must be two intersection points right? but I've only got one. what shall i do? i cannot compute for...
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    Integral calculus: plane areas in rectangular coordinates

    Homework Statement Find the area between y= 1/(x2+1) and the x-axis, from x=0 to x=1 The Attempt at a Solution so when x=0, y=1 and when x=1, y=1/2 next i plot the points, so the intersection of the given equation is (0,1) and (1,1/2) Yh= Y-higher= 1/(x2+1) Yl= Y-lower= 0 the...
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    Charging and discharging capacitor

    I need some help on the interpretation of our laboratory experiment in physics. In our lab experiment we charged and uncharged a capacitor. And here are the things we observe. 1. when one bulb was connected in a circuit across a 4.5 V potential source, the bulb turned on with a bright...
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    Integration by parts evaluation

    ah ok..thank you very much!
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    Integration by parts evaluation

    but , was my answer correct?
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    Integration by parts evaluation

    ok this what I've got... =xax - ∫axdx/lna =xax - 1/lna∫axdx =xax - (1/lna) (ax/lna) =xax - ax/2lna is that right that (lna)(lna) = 2lna? or it is just (lna)(lna) = (lna)(lna)
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    Integration by parts evaluation

    ∫xax u=x du=dx dv=axdx v=ax/lna = xax - ∫axdx/lna is my solution right? my problem now is how to integrate the expression xax - ∫axdx/lna please help..
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    Integration of inverse trigonometric functions

    thank you very much! :smile: ok i will revise my solution to make it more understandable... thank you again..
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    Integration of inverse trigonometric functions

    i solve it and this is my solution.. ∫ (x+2)dx / sqrt (4x-x2) let u= 4x -x2 du=-2(x-2)dx so now the numerator will become [(x-2)+4]dx = ∫ [(x-2)+4]dx / sqrt (4x-x2) = ∫ (x-2)dx / sqrt (4x-x2) + ∫ 4dx / sqrt (4x-x2) let u = 4x -x2 du = -2(x-2)dx...
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