Question 623704
v=100((e^.64t-1)/(e^.64t+1))
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100((e^.64t-1)/(e^.64t+1)) = 50
((e^.64t-1)/(e^.64t+1)) = 0.5
e^.64t-1 = 0.5*(e^.64t + 1) = 0.5e^64t + 0.5
e^.64t - 0.5*e^.64t = 1.5
0.5*e^.64t = 1.5
e^.64t = 3
0.64t = ln(3)
t = ln(3)/0.64
t =~ 1.7166 seconds
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