Find the length of the parabola y^2=4ax cut off the line x=a about the x-axis

Answer 1

do you want the arc length (above and below the x-axis), or the surface when the arc (above or below the axis) is rotated about the x-axis?

Answer 2

2^1/2/a^1/2log|a+1/2|

Answer 3

√2/√a+log|a+√2|