t = 0 at 2:30
minimizing the quantity will also minimize it's square root.
book is correct.
At 2:30 pm, Bob heads north from an intersection at 120 km/h. Alvin is driving east at 96 km/h and reaches the same destination at 5:10 pm. When are they closest to each other.
Is that correct? The answer is supposedly 3:32 PM, so I'm not sure if I understood it incorrectly or if the book had a typo.
Thanks for the assistance!