2) m1*v=(m1+m2)*u; u=(m1*v)/(m1+m2); m1=3*10^4; m2=2*10^4; v=1;
m*v=(m+dv)*u; u=(m*v)/(m+dm); m=500; v=0,2; dm=100;
m2*v2-m1*v1=(m1+m2)*u; u=(m2*v2-m1*v1)/(m1+m2); m1=2; v1=3,5; m2=1; v2=8;
3) (m+M)*U=((m*v1)^2+(M*V2)^2)^0,5; tg(a)=(m*V1)/(M*V2); m=50; V1=1,5; M=100; V2=1