Then the slope of the curve at the tangent point k 1 = the slope of the straight line k2.

The slope of the curve at the tangent point can be used to find the derivative curve, get the derivative function, and then get the tangent slope.

The slope of the straight line can be obtained directly.

Then get an equation, and finally get the required unknown quantity.

Extended data:

Tangency is the positional relationship between a circle on a plane and another geometric shape.

If a straight line intersects a curve at two points, and the two points are infinitely close and tend to overlap, then the straight line is the tangent of the curve at that point. In junior high school mathematics, if a straight line is perpendicular to the radius of a circle and passes through the outer end of the radius of the circle, it is said that the straight line is tangent to the circle.

Here, when "Other Geometry" is a circle or a straight line, there is only one intersection point (common point) between them, and when "Other Geometry" is a polygon, there is only one intersection point between the circle and each side of the polygon. This intersection is the tangent point.

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