When stylus A is moved along curve f₁(x), carriage 1 moves along axis x-x, and slotted link 2 turns about fixed axis D. At this, slider 3 moves along guide 4 which is displaced along axis y-y so that D͞B is always equal to f₂(x) and the distance B͞C=D͞B*tan(α)=f₂(x)xf₁(x). Distance D͞E is taken equal to the unit of the scale in which functions f₂(x) and f₁(x) are plotted.
$1273$LG,MO$