复合函数（续）

Function composition and average rate of change

Summary

For f(x) = 2x^2 - 3x + 1, the average rate of change on [1, 1+h] simplifies to 2h + 1. What is its value when h = 0.5?

For g(x) = 5/x, what is the simplified average rate of change on [1, 1+h]?

f(x) = x + 2 on [-3, 3) and g(x) = x^2 on [-2, 2]. Why can g(f(x)) be undefined for some x in f's domain?

Solving F = 40 + (1/4)N for N gives N = 4F - 160. What is the chirp rate when F = 82?

Which pair writes h(x) = (x^2 + 7)^3 as g(f(x))?

A sphere of radius 4 feet fills so its depth is h = 0.4t. Using V = (pi/3)h^2(24 - h), what is the depth at t = 5 minutes, in feet?

For any two functions f and g, (f o g)(x) equals (g o f)(x).