In this C++ tutorial, you will learn how to find the value of 2 raised to given number using exp2() function of cmath, with syntax and examples.

C++ exp2()

C++ exp2() returns the value of 2 raised to given number (argument).

exp2(x) = 2^x

Syntax

The syntax of C++ exp2() is

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exp2(x)

where

ParameterDescription
xA double, float, long double, or any integral type value.

Returns

The return value depends on the type of value passed for parameter x.

The return value of exp2(x) is

  • double if x is double or integral type.
  • float if x is float.
  • long double if x is long double.

The synopsis of exp2() function is

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double exp2(double x);
float exp2(float x);
long double exp2(long double x);
double exp2(T x); // for integral type argument values

exp2() is a function of cmath library. Include cmath library in the program, if using exp2() function.

Example

In this example, we read a value from user into variable x, and find the value of 2 raised to this number x, using exp2() function.

C++ Program

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#include <iostream>
#include<cmath>
using namespace std;

int main() {
    double x;
    cout << "Enter a number : ";
    cin >> x;
    
    double result = exp2(x);
    cout << "exp2(" << x << ") : " << result << endl;
}

Output

Enter a number : 1
exp2(1) : 2
Program ended with exit code: 0
Enter a number : 10
exp2(10) : 1024
Program ended with exit code: 0
Enter a number : -3
exp2(-3) : 0.125
Program ended with exit code: 0

Conclusion

In this C++ Tutorial, we learned the syntax of C++ exp2(), and how to use this function to find the value of 2 raised to given number, with the help of examples.