[size=100][size=150][b][color=#980000][size=200]Type in parametric equations (in terms of t) of any curves . [br]You can also change starting point (lower t) and the ending point (upper t) in the curve . The default values are t=0 to t=6.28. You can type in any numbers from -20 to 20. [br]Two sketch 2D curves, type 0 for z. [br]The integral represents the arc length formula of the curve from point A to B. [br]You can verify the answers by hand calculation. [/size][/color][/b][/size][/size]