quá dễ
bài 1:
uses crt;
var x,z:integer;
bt:real;
begin
clrscr;
write('x='); readln(x);
write('z='); readln(z);
bt:=(abs(sqr(x)-1))/(z-1/x);
writeln(bt:4:2);
readln;
end.
bài 2:
uses crt;
var a,b,dt,cv:real;
begin
clrscr;
repeat
write('nhap chieu dai:'); readln(a);
write('nhap chieu rong:'); readln(b);
if (a<=b) or (a<=0) or (b<=0) then writeln('ban da nhap sai, yeu cau ban nhap lai');
until (a>b) and (a>0) and (b>0);
cv:=(a+b)*2;
writeln('chu vi=',cv:4:2);
dt:=a*b;
writeln('dien tich=',dt:4:2);
readln;
end.
bài 3:
uses crt;
var r,dt:real;
begin
clrscr;
repeat
write('nhap ban kinh r='); readln(r);
if r<=0 then writeln('ban da nhap sai , yeu cau ban nhap lai');
until r>0;
dt:=sqr(r)*pi;
writeln('dien tich=',dt:4:2);
readln;
end.