Two highways are perpendicular to each other imagine them to be along the x-axis and the y-axis, respectively. At the instant t = 0, a police car P is at a distance d = 400 m from the intersection and moving at speed of 8 km//h towards it at a speed of 60 km//h along they y-axis. The minimum distance between the cars is

Two highways are perpendicular to each other imagine them to be along

1.	Two highways are perpendicular to each other imagine them to be along the x-axis and the y-axis, respectively. At the instant t = 0, a police car P is at a distance d = 400 m from the intersection and moving at speed of 8 km//h towards it at a speed of 60 km//h along they y-axis. The minimum distance between the cars is
Answer» `300 m` `240 m` `180 m` `120 m` Solution :If s be their separation at TIME t then, `s^(2) = (0.4-80t)^(2) + (0.6-60t)^(2)` where t is in hour, s in KM. Minimise s using CALCULUS.

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