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...

a) 6
b) 1/4
c) 1/2 
a) 6
b)  1/4
c) 1/2 = square root of t is
1/2(square root of t) 
Thank you very much for the clarification, could you explain to me how you got 1/2 in c please??

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