Slope, also known as "angle coefficient", is the tangent of the positive included angle of a straight line relative to the horizontal axis, reflecting the inclination of the straight line relative to the horizontal plane. The tangent value of the angle formed by a straight line and the positive and semi-axis directions of the horizontal coordinate axis of the plane rectangular coordinate system is the slope of the straight line relative to the coordinate system.
If the straight line is perpendicular to the X axis, then the tangent of the right angle is tan90, so the straight line has no slope (it can also be said that the slope of the straight line is infinite). When the slope of the straight line L exists, for the linear function y=kx+b (oblique section), k is the slope of the function image.
Slope of different scenes
1. In analytic geometry, it is necessary to study straight lines through the coordinates of points and the straight line equation obtained through coordinate calculation, so that the equation is simpler in form. If only the concept of dip angle is used, it is actually equivalent to arctan k, which is difficult to get directly through coordinate calculation, making the equation form complicated.
2. In the coordinate plane, every straight line has a unique inclination, but not every straight line has a slope. A straight line with an inclination angle of 90 (that is, the vertical line of the X axis) has no slope. In the future study, it is often necessary to discuss whether a straight line has a slope point.