IŽll try to explain this problem. Trying to solve this for the last 40minutes now.
Equation: y = x^(0,5)
The area under this equation starts to rotate around the X-axis and gives you the rotational Volume (B).
When calculating the above mentioned volume: Int: from (a = 0) to (b), There is a line from the point b parallell to the X-axis ( called line d), that line crosses the y-axis. The area between: Y-axis; This line (d), and the area "above" the y = x^0,5 graph starts to rotate around the y axis. This gives you volume (A).
Find x when these areas have the same volumes ( A = B).
The equation for calculating volume rotating around X-axis is:
INT: (pi)*(y^2):dx from a to b (on the x-axis as limes a = 0)
The equation for calculating volume rotating around y-axis is: Int:2*pi*xy:dx from a to b (on the X-axis ALSOOO).
At first I thought, never mind the rotation, just solve so the areas a equal, but that was not very clever, points further from the axises give larger values for volume then closer points do.
I keep getting the answer x = 0,625^2 but that is wrong, THE CORRECT SOLUTION IS (6.25;2.5)
Hope I discribed this problem understandably.