speed of u km/h and then uses y hours to walk back to A at v km/h.
1.1:Find y in terms of u and d.
1.2:Find the average speed for the whole journey of the boy in terms of u and v.
請列式~~~thx!!
更新1:
eelyw: 咁1.1題既式係咪姐係好似你果條: u=d/x................(1) v=d/y................(2) 咁= =但我都係唔係幾明
更新2:
sor,打少左1題: h既2次方+k既2次方 ------------------------- T=2兀乘 g既平方根
更新3:
sor果題打得唔好,再打多次= = 姐係T=2兀乘 g既平方根分之h既2次方+k既2次方 thx~~~