Câu 21.
KQ la 15
Câu 22.
If a=5 then
`\quad` begin
`\qquad` a:=d+1;
`\qquad ` b:=2;
`\quad ` end
else a:=d+2;
Câu 23.
Program Giai_phuong_trinh;
Uses crt;
Var a,b,x:real;
Begin
Clrscr;
Write ('Nhap a= '); readln(a);
Write ('Nhap b= ');readln(b);
If a=0 then
`\qquad` If b=0 then
`\qquad` Writeln('Phuong trinh vo so nghiem')
`\qquad` Else
`\qquad` writeln('Phuong trinh vo nghiem')
Else
`\qquad ` Writeln('Phuong trinh co nghiem x=',-b/a);
`\qquad ` Readln;
End.
