title: Conditions for smooth cubic bezier curve
body: <p>I have the start and end points and the values of the slope of the curve at those points.
  Now I have to draw a "smooth 2D bezier curve" through the two given points.
  Now how to locate the two control points to achieve this. Is there any way for it? I know that the control points must lie on the tangents at the respective start and end points.</p>
  
  <ul>
  <li>Note:By "smooth curve", I meant that there should be no steep curves or turnings in the final plot.</li>
  </ul>