11. How to declare the complex number?

1. 1. complex(5,6)

   
   
   

   2. (5,6i)

   
   
   

   3. (5,6)

   
   
   

   4. All of above

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   We can declare the complex number by using complex(5,6) where 5 is a real number and 6 is imaginary part.

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12. What is the output of this program?
    

    #include <iostream>
        #include <complex>
        using namespace std;
        int main() 
        {
           complex<double> Comp1(3.0, 9.0), Comp2;
           Comp2 = pow(Comp1, 2.0);
           cout << Comp2;
           return 0;          
        }
    

1. 1. (3.0, 9.0)

   
   
   

   2. (3.0, 2.0)

   
   
   

   3. (9.0, 3.0)

   
   
   

   4. (-72,54)

   
   
   

   5. (-54,72)

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   In this program, we are finding the square of the complex number.

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13. How many real types are there in complex numbers?

1. 1. 4

   
   
   

   2. 3

   
   
   

   3. 2

   
   
   

   4. 1

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   There are three real types in complex numbers. They are float complex, double complex, long double complex.

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14. What is the output of this program?
    

    #include <iostream>
        #include <complex>
        using namespace std;
        int main()
        {
            complex<double> Comp_double(4, 6);
            complex<int> Comp_int(7, 8);
            Comp_double *= 2;
            Comp_double = Comp_int;
            cout << Comp_double;
            return 0;
        }
    

1. 1. (7,8)

   
   
   

   2. (4,6)

   
   
   

   3. (8,7)

   
   
   

   4. (6,4)

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   We are just copying the value of Comp_int into Comp_double, So it’s printing as (7,8).

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15. Which header file is used to declare the complex number?

1. 1. complex number

   
   
   

   2. complexnum

   
   
   

   3. complex

   
   
   

   4. All of above

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   complex

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