Question

Assume that n is 5 and k is 2. Which of the Boolean expressions are true? 0! (0 <= n && n <= k) n >= 0 && k > 0 05 < n && n < k || k < 10 0 <= n || n < k ! (n <= 5) O 0 <= k <n

Answer 1

Here is the solution, if you have any doubts then you can write in the comment section.

Please give feedback.

Solution: n=5, k=2

(1) !(0<=n && n<=k) true

Here 0<=n is true, n<=k is false And && operator will return true only when both expression results in true, so here both expressions are not true so it results in false and now we have expression !(false), ! alter true to false or false to true, so finally expression result is true.

(2)  (n>=0 && k>0) true

Here n>=0 is true, k>0 is true And && operator will return true only when both expression results in true, so here both expressions are true so it results in true.

(3) (5<n && n<k || k<10) true

Here 5<n is false, n<k is false k<10 is true.

and (&&) operator will return true only when both expressions results in true.

or( || )operator will return true if at least 1 argument is true.

So here 1 argument is true so it results in true.

(4) (0<=n || n<k) true

Here 0<=n is true, n<k is false.

or( || )operator will return true if atleast 1 argument is true.

So here 1 argument is true so it results in true.

(5) !(n<=5) false

Here n<=5 is true and !(n<=5) becomes !(true) so it results in false.

(6) (0<=k<n) (It depends on language) in c++ it results true, in java it results compile-time error.

According to java :

It is not a valid Boolean expression, it results in a compile-time error. because 0<=k will result in true and now (true<n) which is not a valid comparison.

According to c++ :

It is a valid Boolean expression because 0<=k will result in 1 and now (1<n) returns 1 which means true.

Basically we can say this is an invalid Boolean Expression because Boolean Expression compares as long as the type of 2 operands is the same, but as 1st comparison results in true and now operands true and n, so incompatible type, so it results in an error.

Thank You!