# How to use sqrt function in C++

Mathmetical function are those functions which are used for calculation like sin(X) used to find squareroot of the number. To use the math library functions, we must include the header file

“#include<math.h> “ in C++.

# Constructor with sqrt function in C++

Most of the mathematical functions are placed in `math.h`

header file. sqrt returns the positive square root of floating point .Mathmetical functions like abs, sin, cos, sqrt etc.

# Program to count the characters in the string

String is a series of characters and it can be delimited using double quotes(“”). By using character array we can represent a sequence of characters in C++. Character arrays has being able to query their length, they themselves are not good enough to support the range of operations we may like to perform on string.

# Copy Constructor in C++

Copy constructor is used to copy the value of one object to another object. We used the copy constructor like “ counterrr(counterrr &ob)”. We can declare and initialize an object from another object like “counterrr c2(c1)”.We create two objects that means counterrr c1 and c2 .

# Arrays of objects in C++

An array is a non-primitive data type whose members (variables)are of the same type and stored in continuous memory functions, just as one can create an array of any basic data type, one can also create arrays of objects.