It can be seen that (-∞, 0) monotonically increases; (0, +∞) monotonically decreasing

Choose B.

2. This is a parabola with a downward opening, and the axis of symmetry x=-3/4.

It can be seen that the increased interval is (-∞, -3/4).

Choose C, 2, the first question. It can be discussed in categories. When x is negative, y=x, which is increasing function. Similarly, when x is non-negative and y=-x, it is a decreasing function. So choose D.

The second question, first of all, can be determined that its opening is downward and its symmetry axis (x=-b/2a) is 3/4. So choose the answer A, 1, the increase and decrease function problem of senior one mathematics, and answer it carefully, with a score of 10.

1. function y= negative √x? In the interval (-∞, +∞), it is:

Increasing function b is neither increasing function nor subtraction function c, and subtraction function d is both increasing function and subtraction function.

2. Function y=-2x? The monotonic increasing interval of +3x+ 1 is:

A(-∞，3/4 B3/4，+∞) C(-∞，-3/4 D-3/4，+∞)