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Homework Statement
find the velocity vector for the time t=2s
i have given r(t)=
(50*sin((1/2)*t)*cos ((1/4)t),
50*sin((1/2)*t)*sin((1/4)t))
Homework Equations
i also know that r(t)=
(50*sin(k*t)*cos (1/2k*t),
50*sin(k*t)*sin(1/2k*t))
where k = 0,5s^{1}
The Attempt at a Solution
so i tried solving it and my attempt is shown in the attachment where i got the result
v(2)=6,8;15,7
but someone said it has to be solved with the following results
25m/s*[0,272449, 0,62826] so im quite confused now..
so i dont know what to do and HOPE VERY MUCH someone will check my result v(2)=6,8;15,7 and tell me if its right or not and if so what i can do to get the right result
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