uses math; begin if not(isnan(nan)) then begin writeln('error 1'); halt(1); end; if not(isinfinite(infinity)) then begin writeln('error 2'); halt(1); end; if isnan(12341234) then begin writeln('error 3'); halt(1); end; if isinfinite(0) then begin writeln('error 4'); halt(1); end; if isinfinite(12341234) then begin writeln('error 5'); halt(1); end; end.