
а) var a:array[1..3] of integer;
s, i: integer;
begin
begin
writeln('Vvedite chislo', i - );
readln(a[i]);
end;
s:=0
for i:=1 to 3 do
begin
if a[i] mod 2=0 then
s:=s+a[i]
end;
writeln(s);
readln();
end.
б) var a:array[1..3] of integer;
s, i: integer;
begin
for i:=1 to 3 do
begin
writeln('Vvedite chislo', i - );
readln(a[i]);
end;
s:=0
for i:=1 to 3 do
begin
if a[i]<0 then
write(a[i], ' ')
end;
readln();
end.
в) var a:array[1..3] of integer;
s, i: integer;
begin
for i:=1 to 3 do
begin
writeln('Vvedite chislo', i - );
readln(a[i]);
end;
s:=1
for i:=1 to 3 do
begin
if a[i] mod 3=0 then
s:=a[i]*a[i];
end;
writeln(s);
readln();
end.
![\displaystyle a_1= \frac{3}{2}; \\ \\ a_{i-1}=\frac{3^{i-1}\cdot (i-1)!}{[2(i-1)]!}; \\ \\ a_i=\frac{3^i\cdot i!}{(2i)!} = \frac{3\cdot3^{i-1}\cdot i\cdot(i-1)!}{2 i\cdot(2i-1)\cdot(2i)!}={ \frac{3i}{2i\cdot(2i-1)}\cdot a_{i-1}=\frac{3}{4i-2}\cdot a_{i-1}](/tpl/images/0829/8194/4eada.png)