II.
>> syms vx ix vC vL vxn ixn vCn vLn k a w t L C
>>ix=k*t^2*exp(-a*t)*sin(w*t)
>> ixn = subs(ix,[k a w],[3 2 1])
>> ezplot(ixn,[0,10])
>> vL=L*diff(ix,t)
>> vC=(1/C)*int(ix,t,0,t);
>>vx = vC + vL;
>> vLn=subs(vL,[k a w L C],[3 2 1 0.5 1]);
>> vCn=subs(vC,[k a w L C],[3 2 1 0.5 1]);
>> vxn=subs(vx,[k a w L C],[3 2 1 0.5 1]);
>> figure
>> ezplot(vLn,[0,10])
>> hold on
>> ezplot(vCn,[0,10])
>> ezplot(vxn,[0,10])
>> legend('vLn','vCn','vxn')