# Calculus (pleas help I really need to check this)

posted by Catherine

Assume that each of the follwing functions gives the position of an object at time t. Find the velocities indicated by setting up and evaluating a limt algebraically.

(a) s(t) = 3t^2, Find v(-1).
(b) s(t) = 1/t , Find v(2).
(c) s(t) = square root of t, Find v(1).

The answers that I got were the following...
a)3
b)1/2
c)1

I did them another way and the answers I got were
a)-6
b) -(1/4)
c) I didn't really get any answers here.

Please tell me which answers are right or if any of them are right...

1. Reiny

a) -6
b) -1/4
c) 1/2

2. Ralph

a) -6
b) - 1/4
c) 1/2 = square root of t is
1/2(square root of t)

3. Catherine

Thank you very much for the clarification, could you explain to me how you got 1/2 in c please??

4. Reiny

s(t) = √t = t(1/2)
s '(t) = (1/2)t^(-1/2) = 1/(2√t)
s '(1) = 1/(2√1) = 1/2

5. Catherine

Could you please tell me how to do it evaluating the limt algebraically? I'm trying to do it and I can't get it....

## Similar Questions

1. ### Calculus

Assume that each of the follwing functions gives the position of an object at time t. Find the velocities indicated by setting up and evaluating a limt algebraically. (a) s(t) = 3t^2, Find v(-1). (b) s(t) = 1/t , Find v(2). (c) s(t) …

Hello I'm reposting this question because right now it's at the bottom and I don't think I will get an answer. Assume that the follwing function gives the position of an object at time t. Find the velocity indicated by setting up and …
3. ### Math

An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND …

An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND …

An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND …
6. ### Big MATH Help needed

An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND …
7. ### Calculus

An object at rest begins moving horizontally on the x-axis, starting at position x(t) = 0 feet at time t = 0 seconds.Suppose, after exactly 2 seconds we measure the position of the object to be 3 feet to the right of the origin AND …
8. ### Calculus

An object is traveling along the x axis so that its speed is given by v(t)=t^2-7t+10 m/s. (a) Find the times when the object is at rest. (b) Find the acceleration at both of these times. Interpret the acceleration in terms of the motion …
9. ### Calculus

An object is traveling along the x axis so that its speed is given by v(t)=t^2-7t+10 m/s. (a) Find the times when the object is at rest. (b) Find the acceleration at both of these times. Interpret the acceleration in terms of the motion …
10. ### Calculus

The position, p(t), of an object at time t is given. Find the instantaneous velocity at the indicated time c. Also determine whether it is moving forward, backward, or neither at time c. p(t)=2-1/t at c=3

More Similar Questions