In C++, boolean is a data type that can have two possible values: true or false.
Here's an example of how to declare and assign a boolean variable in C++:
``c++
bool isStudent = true;
Here's an example of how to use boolean expressions in C++:
c++
int num1 = 5;
int num2 = 10;
bool isLarger = num1 > num2;
bool isEqual = num1 == num2;
cout << "Is num1 larger than num2? " << isLarger << endl; // prints "Is num1 larger than num2? 0" (false)
cout << "Are num1 and num2 equal? " << isEqual << endl; // prints "Are num1 and num2 equal? 0" (false)
`
In the example above, we declare and assign two integer variables num1 and num2. We then use boolean expressions to determine if num1 is greater than num2 (isLarger) and if num1 is equal to num2 (isEqual).
We then use cout to print out the values of isLarger and isEqual. Since neither of these boolean expressions were true (because num1 is not greater than num2 nor equal to num2), we get the value of 0 (false) when printing out these variables using the <<` operator.