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age 23
visits member for 3 years, 5 months
seen Jun 30 '13 at 13:58

"An expert is a person who has made all the mistakes that can be made in a very narrow field." Niels Bohr


Apr
29
accepted Find the area of the surface obtained by rotating the curve about the x axis
Apr
29
asked Find the arc length of the cardioid: r = 3-3cos θ
Mar
8
accepted How to sketch the curve of parametric equations
Mar
8
comment How to sketch the curve of parametric equations
alright. thanks for all your help :)
Mar
8
comment How to sketch the curve of parametric equations
i guess i was hoping for a "fast" solution, but i now know with parametric equations, there doesn't appear to be any simple or straightforward method.
Mar
8
comment How to sketch the curve of parametric equations
very informative! ok so basically, you want to analyze exactly what the functions x and y are doing and that will give you the complete curve. and the part of the unit circle that is graphed is the right half.
Mar
8
comment How to sketch the curve of parametric equations
sorry i had to finish editing my response
Mar
8
comment How to sketch the curve of parametric equations
i see now. so sin θ >= 0 and then sin θ <= 1. so x >= 0 and <=1?
Mar
8
comment How to sketch the curve of parametric equations
oh ok. so i could create a table of various points for t and then find the corresponding x and y values to determine the curve?
Mar
8
comment How to sketch the curve of parametric equations
oh ok. so essentially, you can just plot the initial point, the ending point to get the shape of the curve, and a point in between to determine the direction of the curve?
Mar
8
asked How to sketch the curve of parametric equations
Mar
8
comment Find the area of the surface obtained by rotating the curve about the x axis
ahh now i see! thanks
Mar
7
comment Find the area of the surface obtained by rotating the curve about the x axis
After doing that I get: the integral from 0 to 1 of [(-2/pi) sqr(1 + u^2pi) du]. Would I have to do a trig substitution?
Mar
7
asked Find the area of the surface obtained by rotating the curve about the x axis
Mar
3
accepted Determining a closed-form solution for the following sum
Mar
3
comment Determining a closed-form solution for the following sum
thanks! that cleared it up
Mar
3
comment Determining a closed-form solution for the following sum
but when evaluating the first summation, it does not need to be multiplied by (n+1) because you are plugging in for i directly?
Mar
3
comment Determining a closed-form solution for the following sum
in the second summation, are you adding n+1 because the index starts at 0 and not 1?
Mar
3
revised Determining a closed-form solution for the following sum
added 1 characters in body
Mar
3
comment Determining a closed-form solution for the following sum
the second one.