Which is equal, to 2 + 6 + 4 or 12, which should be our answer to the first part.
All right. What about f(x^2)?
Now, don't let it confuse you that this is a variable now.
And moreover, that it's the same variable x that we see up here in the definition
of our function. Remember, what ever is inside these
parenthesis is our input. Which means, we need to put it in over,
and here. That is this is = 2-3 * that input, or *
x^2 + that input, or x^2. Quantity ^2, which is =.
2 - 3x^2 + x^4. which would be our answer to the second
part. All right, what about this third one
here, g of 3? Now we'll start working with our function g.
So 3 then is going to be our input. Which means looking here on the right,
we're going to plug it in here and we're going to plug it in here.
That is, this is equal to the input which is 3.
+ 4 / 2 times the input or 2 * 3 - 1, which is equal to, 7 / 6 - 1, which is 5,
which would be our answer to the third part.
And finally, what about g(x+1)? Again, don't let it confuse you, that you see a
variable, here, inside the parentheses. And moreover, that it's the same
variable, as we have up here, in the definition of g.
Remember, whatever is inside the parenthesis is our input.
So this whole quantity, x + 1, is our input.
Which means over here on the right, we're going to plug it in here, and here.
Namely, this is equal to the input, or x + 1 + 4 / 2 * the input, or 2 * x + 1 and
then - 1, which = x + 5 / now distributing our 2, we have 2x + 2 - 1,
which is equal to x + 5 / 2x + 1. Which would be our last answer.
And this is how we evaluate functions. Whatever we see inside the parenthesis,
we put in as our input. Thank you and we'll see you next time.
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