Theorem corresponding to "same increase but different decrease";

1. Let the function y=f(x) consist of functions y=g(u) and u=h(x), that is, f(x)=g[h(x)] (note that the corresponding laws of f, g and h are different). If the function y=g(u) has an interval (a),

What needs special attention here is the condition that "and the function values of u=h(x) in the interval (c, d) are all in the interval (a, b)".

2. Let the function y=f(x) consist of functions y=g(u) and u=h(x), that is, f(x)=g[h(x)] (note that the corresponding laws of f, g and h are different). If the function y=g(u) has an interval (a, b), it is.

3. Let the function y=f(x) consist of functions y=g(u) and u=h(x), that is, f(x)=g[h(x)] (note that the corresponding laws of f, g and h are different). If the function y=g(u) has an interval (a, b), it is.

4. Let the function y=f(x) consist of functions y=g(u) and u=h(x), that is, f(x)=g[h(x)] (note that the corresponding laws of f, g and h are different). If the function y=g(u) has an interval (a, b), it is.