Joke Collection Website - News headlines - Urgent, ask for advice on a mathematical function problem, thank you: A parking lot found in the trial operation stage that the parking fee of each sub-car does not exceed 5 yuan time.

Urgent, ask for advice on a mathematical function problem, thank you: A parking lot found in the trial operation stage that the parking fee of each sub-car does not exceed 5 yuan time.

(1)y=144x-8, and y≥2512.

Therefore, x≥2.3 ,∵x only takes the integer ∴x at least not lower than 3 yuan.

(2) y = [144-12 * (x-5)] x-8.

(3) from (2), -(3x? -51x+2)*4

Therefore, the net income is the largest when x=8 or x=9

Because there are more cars to park, x=8

The net income at this time is y=784.