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

A). doSomething();

B). call doSomething;

C). doSomething[];

D). invoke(doSomething);

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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'); } };

Which of the following is an example of using a function as a return value?

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

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A). 7

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How do you assign a function to a variable in JavaScript?

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

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