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So some will tell you a function really isn't a function unless you're returning a value, so it functions

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really have the three parts, they have the input.

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So this is the data that's sent into the function, the code that gets a run and then also the output.

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And this is commonly a value that's returned by the function example.

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We've got two numbers that are being passed in and we're returning back the two values, but we're adding

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them together.

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So we're doing something with the content that's being passed in and returning back, something that's

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been computed out of the function, something different.

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So we've got a quick math option.

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And math is one of the great examples that we can use because it's really simple and we can show you

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how you can multiply so you can create a function to do multiplication of any two numbers.

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And also notice as well that there is no semicolon at the end.

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The semicolon is within the block of code and it's straight after within the return.

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So we're all we're doing is we're taking in the two values and then we're taking X times Y and we're

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returning back that computed value.

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So there is a challenge in this lesson and that's to create a function that multiplies two values and

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returns the result.

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And ideally, what we want to do is put it into the console.

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So something like this where we're calling a function called multiplier and we're passing in the two

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numbers and then we're seeing the result being returned back.

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So this could be 10 and five or any combination that return back 50.

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So go ahead and pause the video, try it out.

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And this is a quick peek at what the solution is and I'll walk you through it coming up.

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I hope you had an opportunity to try this out for yourself.

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And this was a really quick, short example of how to use a function.

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And this can be number one.

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So we can equal that to one hundred and number two can be two hundred, create our function, taking

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in value eight and value B and then returning back.

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The result, you can also set up a temporary holder for that as well.

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So you could take A and B and then return back temp or you could do it all within one statement.

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The result is going to be the same.

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And then next we need to consider log out the value of multiplier and we have them as variables so we

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can take value of number one and number two and we can see what gets output in the console.

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So it gets the solution output in the console.

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And we also saw within the example as well that we can create the function in a different format as

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well.

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And there's going to be more on this coming up.

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And we'll just call this multiplier two and then we're going to equal that to an anonymous function,

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taking in the two values, the two parameters to return back A times B or if we wanted to, we could

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write it within the same way as well.

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So all the block of the code that's inside is the same thing.

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It doesn't matter how you rate it a function expression, you do have to define it before you try to

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use it.

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Otherwise you're going to get an error in your code.

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So if I do try to do it like this, you're going to see it throws an error.

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So that means that we do need to have the function and we have to define it before we try to use it.

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So that's the real difference between the two, is that this one we can use at any point so we could

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even use it before we're defining the function and we're not going to throw any errors.

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And of course, we are going to be covering this in a little bit more detail coming up.

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So go ahead and try that out.

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And if you did the second option as well.

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So this is valid and an invalid format as well for a solution.