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simplifying expressions - How to make Mathematica Simplify?


Let us define


r1 = 1;r2 = 2;

and


beta2[t_] := {r1*Cos[2*Pi*t], r2*Sin[2*Pi*t]}
beta1[t_] := beta2[t + 4.8*t^2*(t - 1)^2]

k[v_] := If[Norm[v] > 0, v/Sqrt[Norm[v]], 0]

with


q2[t_] :=  FunctionExpand[k[beta2'[t]], Assumptions -> t \[Element] Reals]

q1[t_] := FunctionExpand[k[beta1'[t]], Assumptions -> t \[Element] Reals]

Now when I call


 q1'[3]


I get


{4.56985 + 0.157049 (10.2293 Derivative[1][Abs][-5.97566] - 40.9174 Derivative[1][Abs][-3.88322]), -28.1291 + 0.102057 (10.2293 Derivative[1][Abs][-5.97566] - 40.9174 Derivative[1][Abs][-3.88322])}


Question



How to simplify this expression?





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