I don't know how many functions I have. Let's talk about what I came into contact with in middle school:

1, proportional function y = kx

2. Inverse proportional function y = k/x

3. linear function y = kx+b (k is not 0, but b can)

4. Quadratic function y = ax? +bx+c(a is not 0)

5. Trigonometric functions (8 kinds of * * *, 4 kinds of junior high school and 6 kinds of senior high school)

Include sine, cosine, tangent, cotangent, secant and cotangent.

6. Exponential function y = x A (A is not 0)

7, logarithmic function y = logax (x is not 0)

Ask if you need to take pictures.