{s=1-1/1+1/3-1/5+.....} var i,n,z:integer; s: real; begin writeln('Введите n'); readln(n); s:=1; z:=1; for i:=1 to n-1 do begin z:=z*(-1); s:=s+z/(2*i-1); end; writeln(s); end.
<span>A = (5 < 10) = true B = (2 = 2) = true С = (4 < 2) = false </span><span>(A and B) or C ↔ (A or C) and (A or not B) </span>⇒ (true and true) or false ↔ (true or false) and (true or not true) ⇒ true or false ↔ true and true ⇒ true ↔ true ⇒ true