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Introduction to the basic knowledge of junior high school mathematics
1, knowledge point: the basic concept of a quadratic equation.

The constant term of the unary quadratic equation 3x2+5x-2=0 is -2.

The coefficient of the primary term of the unary quadratic equation 3x2+4x-2=0 is 4 and the constant term is -2.

The quadratic term coefficient of the unary quadratic equation 3x2-5x-7=0 is 3 and the constant term is -7.

The equation 3x(x- 1)-2=-4x is transformed into the general formula 3x2-x-2=0.

2. Knowledge points: Cartesian coordinate system and the position of points.

In the cartesian coordinate system, the point (3,0) is on the y axis.

In rectangular coordinate system, the abscissa of any point on the X axis is 0.

In rectangular coordinate system, point A (1, 1) is in the first quadrant.

In the angular coordinate system, point A (-2,3) is in the fourth quadrant.

In rectangular coordinate system, the point (-2, 1) is in the second quadrant.

3. Knowledge point: Find the function value from the values of known independent variables.

When x=2, the value of function y= is 1.

When x=3, the value of function y= is 1.

When x=- 1, the value of function y= is 1.

4. Knowledge points: the concept and nature of basic functions.

The function y=-8x is a linear function.

Function y=4x+ 1 proportional function.

Function is an inverse proportional function.

The opening of parabola y=-3(x-2)2-5 is downward.

The symmetry axis of parabola y=4(x-3)2- 10 is x=3.

The vertex coordinate of parabola is (1, 2).

The images of the inverse proportional function are in the first and third quadrants.