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Integral volume problems (1 Viewer)
- Thread starter Sien
- Start date
Q9) Well the ellipse has a semi major and semi minor of 3 and 4, upon inspection of the graph from the general ellipse equation x^2/a^2 + y^2/b^2 = 1
But as we want to integrate about the X-axis for part a) the limits will be -4 and 4.
V= pi integral of y^2 dx
9x^2 + 16y^2 = 144
16y^2 = 144-9x^2
y^2 = 144/16 - 9/16 x^2
Sub that into the integral, integrate it and sub in the limits from 4 to -4, and you'll get a solution.
b) Sub the limits 3 to -3 for the y axis, and make sure it is the integral of x^2 dy.
I'll do Q10 and the others when I have spare time. Just find the X-intercept of 9-x^2 for Q10, and they will be your limits for X-axis.
But as we want to integrate about the X-axis for part a) the limits will be -4 and 4.
V= pi integral of y^2 dx
9x^2 + 16y^2 = 144
16y^2 = 144-9x^2
y^2 = 144/16 - 9/16 x^2
Sub that into the integral, integrate it and sub in the limits from 4 to -4, and you'll get a solution.
b) Sub the limits 3 to -3 for the y axis, and make sure it is the integral of x^2 dy.
I'll do Q10 and the others when I have spare time. Just find the X-intercept of 9-x^2 for Q10, and they will be your limits for X-axis.
Drsoccerball
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- 2015
Question 12 make a sample equation for the volume
I'm stuck with Qs 9 12 13. Can someone please help with working out. I'm so use to MIF so these questions seems daunting. Thanks
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