program tab_13;
var a,b:integer;
k,z:real;
const h=0.2;
begin
repeat
writeln('vvedite znachenie a');
read(a);
writeln('vvedite znachenie b');
read(b);
until (a<0) and (a=b);
begin
k:=sin(3.4*z*z*z)/cos(3.4*z*z*z)+cos(z+1.2);
if(k>=-1) and(k<=1) then
writeln('z=z',z:6:2,'k=',k:6:2);
z:=z+h;
end;
end.