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

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'); } };

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

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A). performAction(function() { alert('Action!'); });

B). performAction(function { alert('Action!'); });

C). performAction(function() alert('Action!'););

D). performAction(function() alert('Action!'))

What will be the output of the following code? var multiply = (x, y) => x * y; console.log(multiply(3, 4));

A). 12

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What will be the output of the following code? var add = new Function('a', 'b', 'return a + b'); console.log(add(2, 3));

A). 5

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Which of the following is an example of an arrow function assigned to a variable?

A). var add = (a, b) => { return a + b; };

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C). var add = (a, b) => { a + b };

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A). var anon = function() { alert('Anonymous!'); };

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D). var anon = function anonymous() { alert('Anonymous!'); };

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A). function outer() { return function() { alert('Inner'); }; }

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D). function outer() { return function { alert('Inner'); }; }

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

B). var greet = function { alert('Hello'); };

C). function greet() { alert('Hello'); }

D). var greet = function alert('Hello');