Y = -3 f(x+2) - 7 (Function help)

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The discussion centers on evaluating the function y = -3 f(x+2) - 7 using five different function definitions: f(x) = x, f(x) = x^2, f(x) = |x|, f(x) = 1/x, and f(x) = √2. The main challenge is substituting each function into the equation and understanding how to transform the argument. An example is provided using f(x) = x^2, demonstrating that f(x+2) becomes (x+2)^2. After clarification, the user expresses understanding of how to apply the transformations for all five functions. The conversation concludes with the user feeling confident about completing the assignment.
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Hey I am left with this question and I have no clue how to do it

y = -3 f(x+2) - 7 (Function help!)

1. f(x) = x
2. f(x) = x^2
3. f(x) = |x|
4. f(x) = 1/x
5. f(x) = (square root of 2) how do i write that out?

Basically I am suppose to substitute the 5 things into the equation and the graph it. I am confident that I can graph it with no problems. However, I can't do the first part, which is to put the 5 f(x) things into the equation

Help please, its due tomorrow:(
I'll check for replies frequently so if u can help me..GREAT!

Thx in advance guys
 
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No problem! :smile:

If you're unsure about function notation, all you need to know is this: the definition of the function tells you what to do to (how to "transform" or change) the argument (ie the variable) that you are passing into the function. So let's take an example:

If you have a function defined by:

f(x) = x2

then, when you pass the argument 'x' into the function, whatever value it has is squared. Now, what if we evaluate the function for a more complicated argument?

If f(x) = x2, then what is:

f(x+2) ?

Same rule! The function definition is a general statement that whatever argument is passed into the function is squared, not matter what it is.

So f(x+2) = (x+2)2

If you still can't see it, notice that we're just evaluating the function for a different variable, which we could define by u = x + 2. Obviously by definition:

f(u) = u2 = (x+2)2

Well, that example just happens to take care of your # 2. Can you do the rest?
 
yes thanks so much I think I understand all 5 now

THX!
 
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