Q
What will be the output of the following code? var double = function(x) { return x * 2; }; console.log(double(5));

Answer & Solution

Answer: Option A
Solution:
The function double returns x * 2, so console.log(double(5)) outputs 10.
Related Questions on Average

Which of the following is true about functions in JavaScript?

A). Functions can be assigned to variables

B). Functions can be passed as arguments to other functions

C). Functions can be returned from other functions

D). All of the above

What is the output of the following code? var person = { name: 'Alice', greet: function() { return 'Hello, ' + this.name; } }; console.log(person.greet());

A). Hello, Alice

B). Hello, undefined

C). Hello, name

D). undefined

What is the term for a function that is passed as an argument to another function?

A). Callback function

B). Nested function

C). Helper function

D). Inner function

How can you store a function as a property of an object?

A). var obj = { method: function() { alert('Hello'); } };

B). var obj = { method: alert('Hello'); };

C). var obj = { method: function { alert('Hello'); } };

D). var obj = { function() { alert('Hello'); } };

What will be the output of the following code? var sayHi = function() { return 'Hi'; }; console.log(sayHi());

A). Hi

B). undefined

C). sayHi

D). function

How can you invoke a function stored in a variable doSomething?

A). doSomething();

B). call doSomething;

C). doSomething[];

D). invoke(doSomething);

How do you create an Immediately Invoked Function Expression (IIFE)?

A). (function() { alert('IIFE'); })();

B). function() { alert('IIFE'); }();

C). (function { alert('IIFE'); })();

D). function() { alert('IIFE'); };

How do you define a function using a function expression?

A). var myFunc = function() { alert('Hello'); };

B). function myFunc() { alert('Hello'); }

C). var myFunc = function { alert('Hello'); };

D). var myFunc() { alert('Hello'); }

What is the output of the following code? function makeAdder(a) { return function(b) { return a + b; }; } var add5 = makeAdder(5); console.log(add5(2));

A). 7

B). 5

C). add5

D). makeAdder

How can you define a method inside an object?

A). var obj = { method: function() { alert('Hello'); } };

B). var obj = { method() { alert('Hello'); } };

C). Both A and B

D). var obj = { function method() { alert('Hello'); } };