Shanghai science edition eighth grade mathematics first volume catalogue
The knowledge content of the coordinate characteristics of points in the plane in the first volume of the eighth grade mathematics of Shanghai Science Edition
1, the coordinate characteristics of point P(a, b) in each quadrant:
The first quadrant: a>0, b>0; The second quadrant: a
(Note: Quadrants 1 and 3 have the same horizontal and vertical symbols, namely ab>0; Two or four quadrants, with opposite signs, namely AB.
2. Coordinate characteristics of point P(a, b) on the coordinate axis:
On the x axis: a is an arbitrary real number, and b = 0;; On the y axis: b is an arbitrary real number, and a = 0;; Origin of coordinates: a=0, b=0.
(Note: If P(a, b) is on the coordinate axis, then ab = 0;; Conversely, if ab=0, then P(a, b) is on the coordinate axis. )
3. Coordinate characteristics of point P(a, b) on the bisector of two axes: