posted by Aletha on .
After t hours of an 8-hour trip the distance a car travels is modeled by:
D(t)= 10t + (5)/(1+t) - 5
where D(t) is measured in meters.
a) derive a formula for the velocity of the car.
b) how fast is the car moving at 6 hours?
c) derive a formula for the car's acceleration.
b).6 meters (I KNOW this is wrong!)
I just know my answers are wrong if someone could just tell me where I went wrong?
Your derivative, (the velocity), should have been 10 -5(1+t)^2
now substitute t=6 into that.
your acceleration, the second derivative, should be
oops, forgot the divistion sign
first derivative is 10-5/(1+t)^2
for the velocity derivative; I get 5/49 which is .102 meters? That still doesn't sound right.
For the acceleration are you taking the 2nd derivative... because if so; why still have the 10?