Dear Solidworks geeks,

I have drawn a curve in a 2D sketch with this function:

y(x)=50*sin(2*pi*x/550)

and i have drawn a line tangent to the curve at the point x=550 to get the slope the curve at this point, i found the angle of the slope is 29.73 deg.

While taking the derivative of this sine equation to get the slope at point x=550 gives the angle 32.72 deg, the first derivative equation is:

y'(x)=pi/5.5*cos(2pi)

Here is the sketch in solidworks:

do any one knows what is the problem here, is solidwokrs accurate enough to find the slope angle? or Not!! ?

regards,

Fahd