Monday

January 26, 2015

January 26, 2015

Posted by **agora** on Thursday, May 2, 2013 at 5:41am.

(a) at what rate are they approaching or separating at the end of one hour?

(b) At what rate are they approaching or separating at the end of two hours?

(c) When do they cease to approach each other and how far apart are they at that instant

- calculus -
**Steve**, Thursday, May 2, 2013 at 11:37amLet B start at (0,0). Then the positions of the boats at time t are

A(t) = (0,50-25t)

B(t) = (20t,0)

and the distance d is thus

d^2 = (20t)^2 + (50-25t)^2

= 1025t^2 - 2500t + 2500

2d dd/dt = 2050t - 2500

At t=1, d ~= 32

64 dd/dt = 2050-2500

dd/dt = -7.03 km/hr

At t=2, d = 40

80 dd/dt = 4100-2500

dd/dt = +20

dd/dt=0 when t=1.22 so d = 31.23

**Answer this Question**

**Related Questions**

Differential Calculus - At 9am ship B is 65 miles due east of another ship A. ...

CALCULUS!!!!! - At 9am, ship B was 65 miles due east of another ship, A. Ship B ...

calculus - At 9am, ship B was 65 miles due east of another ship, A. Ship B was ...

Calculus - one ship (A) is sailing due south at 16 miles per hour and a second ...

calculus - Optimization At 1:00 PM ship A is 30 miles due south of ship B and is...

calculus - At 1:00 p.m. ship A is 25 km due north of ship B. If ship A is ...

Calculus - At 4 PM ship A is 40 miles due South Ship B. Ship A is sailing due ...

Calculus - At 1:00 p.m. ship A is 25 km due north of ship B. If ship A is ...

Calculus - "At 9am ship A is 50 km east of ship B. Ship A is sailing north at ...

Calc - At noon, ship A is 100 Kilometers due east of ship B, Ship A is sailing ...