Recall that the derivative of a constant is 0.
In geometry, the tangent line (or simply tangent) to a plane curve at a given point is the straight line that "just touches" the curve at that point. Leibniz defined it as the line through a pair of infinitely close points on the curve
6x y³ × 4x² y²
=
24 x¹+² y³+²
=
24x³ y⁵
