What does a delta mean in calculus?
Mainly used for "Difference between two given values", it is used a lot in derivatives.
If we have any line on a graph, its slope is
which can be rewritten as
Now, more interestingly, as these difference gets closer and closer to zero, we can say that we get closer and closer to
Which tells us that the difference in the values are getting really, really, small.
If you think about that, we are shrinking two points down to a point.
If we were to have a curve and have a line pass through only one point on it, then we can call that line is tangent to the curve.
Anyways, I wish you good luck in calculus!