reserve a,b,c,x,y,z for Real;

theorem Th54:
  a >= 0 & b >= 0 implies a*sqrt(b) = sqrt(a^2*b)
proof
  assume that
A1: a>=0 and
A2: b>=0;
  sqrt(a^2)=a by A1,Def2;
  hence thesis by A1,A2,Th29;
end;
