Recent content by TicTacToe

Well, I'll try with a more simple question then, I guess. All hypocycloid can be described as a smaller circle rotating inside a larger, with a point P on the rim of the circle creating the curve. Why is then the smaller circle radius (b) * the angle in the small circle (ϑ) the same as the big...

Could someone give me a hint how the formula s(θ) = (8*(a-b)*b*(sin (aθ/4b))^2)/a is derived. s is the arc length of the astroid's curve. where θ is the angle of the circle with (a-b) radius. Thanks in advance! the formula can be find at http://mathworld.wolfram.com/Hypocycloid.html

Aight, thanks but do you have any else that might help me with the problem?

Alright, I might have the answer to this now but I'm not quite sure. I have integrated the expression: L = ∫ √ (a(2/3)/x(2/3)) dx = = ∫ a(1/3)/x(1/3) dx to [ ∛a * (3/2) * x(2/3) ] Known by the graph on my analog paper a is represented as the max value of x and y, both positive...

Thanks LCKurtz! Now I get the formula: √ (a^(2/3)/x^(2/3)) dx = The length of the curve between two x-values I guess I should integrate this next. I'll do it tomorrow and if I encounter any problems I'll ask for further guidance. Can't really get the hang of those TEX stuff

Homework Statement Calculate the length of the graph/equation: x^(2/3) + y^(2/3) = a^(2/3) The graph is formed as an s.c. asteroid, almost like a diamond. It seems to be some sort of modified unit circle. Homework Equations The length of the graph between x1 and x2 can be described as L=∫...