Một số bài tập tham khảo C++

BÀI TẬP

1 //Tính t0ng S= 1/2 + 1/3 + + 1/n

#include<iostream.h>

main()

{

float n,i; float t=0;

cout<<"Nhap n = ";cin>>n;

for(i=2;i<=n;i++)

t+=float(1/i);

cout<<"Tong S = "<<t<<endl;

}

2 //Tính tong S = 1^2 + 3^2 +…+(2n-1)^2

#include<iostream.h>

main()

{ int n,i;

float t=0;

cout<<"Nhap n = ";cin>>n;

for(i=1;i<2*n;i+=2)

t+=(i*i);

cout<<"Tong S = "<<t<<endl;

}

3 // Tính tích T = 1*4*9*16*….*n2

#include<iostream.h>

main()

{

int n,i;

float t=1;

cout<<"Nhap n = ";cin>>n;

for(i=1;i<=n;i++)

t*=i*i;

cout<<"Tich T = "<<t<<endl;

}

4 // Tính S = 2^2/2! + 2^3/3! + ………+ 2^n/n!

#include<iostream.h>

float giaithua(int n)

{

int i,t=1;

for(i=1;i<=n;i++)

t*=i;

return t;

}

float luythua(int a,int n)

{

int t=1,i;

for(i=0;i<n;i++)

t*=a;

return t;

}

main()

{ int i,x,n;

float t=0; x=2;

cout<<"Nhap n = ";cin>>n;

for(i=2;i<=n;i++)

t+=(luythua(x,i)/giaithua(i));

cout<<"T= "<<t;

}

5 // Tinh tong S= 1+3+5+ +(2*n+1), n la so nguyen duong

#include<iostream.h>

#include<conio.h>

{ int i,n,s=0;

cout<<"Nhap n= "; cin>>n;

for(i=0;i<=n;i++)

s+=(2*i+1);

cout<<"Tong S = "<<s<<endl;

}

6 // Tinh tong S= 2+4+6+ +2*n, n la so nguyen duong

#include<iostream.h>

#include<conio.h>

main()

{ int i,n,s=0;

cout<<"Nhap n= ";

cin>>n;

for(i=1;i<=n;i++)

s+=(2*i);

cout<<"Tong S = "<<s<<endl;

}

7 // Tinh tong S=13+23+ +n3, n la so nguyen duong

#include<iostream.h>

#include<conio.h>

main()

{ int i,n,s=0;

cout<<"Nhap n= "; cin>>n;

for(i=1;i<=n;i++)

s+=i*i+i;

cout<<"Tong S= "<<s<<endl;

}

8 // Tinh tong S=1*2*3+2*3*4+ +n*(n+1)*(n+2)

#include<conio.h>

main()

{ int i,n,s=0;

cout<<"Nhap n= "; cin>>n;

for(i=1;i<=n;i++)

s+=i*(i+1)*(i+2);

cout<<"Tong S = "<<s<<endl;

}

9 // tinh tong s=1/2!+2/3!+ +n/(n+1)!

#include<iostream.h>

float giaithua(int n)

{ int i,t=1;

for(i=1;i<=n;i++)

t*=i;

return t;

}

main()

{ int i,n; float s=0;

cout<<"Nhap n = "; cin>>n;

for(i=1;i<=n;i++)

s+=(i/giaithua(i+1));

cout<<s;

}

10 // tinh tong s= 1.1!+2.2!+ +n.n!

#include<iostream.h>

float giaithua(int n)

{ int i,t=1;

for(i=1;i<=n;i++)

t*=i;

return t;

}

main()

{ int i,n; float s=0;

cout<<"Nhap n = "; cin>>n;

for(i=1;i<=n;i++)

s+=(i*giaithua(i));

cout<<s;

}

11 // S=1/1.2+1/2.3+ +1/n(n+1)

#include<iostream.h>

main()

{ int i,n; float s=0;

cout<<"Nhap n = "; cin>>n;

for(i=1;i<=n;i++)

s+=(1.0/(i*(i+1)));

cout<<s<<endl;

}

12 // S=1/1^2+1/2^2+ 1/n^2

#include<iostream.h>

float luythua(int a,int n)

{ int i,t=1;

for(i=1;i<=n;i++) t*=a;

return t;

}

main()

{ int i,x=2,n;

float s=0;

cout<<"Nhap n = "; cin>>n;

for(i=1;i<=n;i++)

s+=(1.0/(luythua(i,x))); cout<<s<<endl; }