问题描述:
要快 ,在线等!!!!!!!!!!!!!!!!
问题解答:
路程=时间*速度所以S=300T0<=S<=1318所以0<=300T<=13180<=T<=659/150所以S=300T,其中0<=T<=659/150
S=300t(0小于等于x小于等于659/150)
S=1318-300T