domain and range of a transformed function

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This is the original function; y=f(x) with a domain of -3<_ x <_ 3 and a range of 0 <_ y <_ 3.

Now I was asked to find the range and domain of y=f(x-2).

So I said -3<_ x <_ 3 and 1<_ y <_ 5.

But the answer was -1<_ x <_ 5 and 0 <_ y <_ 3.

I don't get it. Am I supposed to keep the same range, not the domain? Is that what it is? Why is my answer wrong?

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3
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The domain is the set of numbers you plug into $f$. Here, the number you plug into $f$ needs to be between $-3$ and $3$. Since the number you're plugging into $f$ is $x-2$, this means you need $-3 \le x-2 \le 3$, which is equivalent to $-1 \le x \le 5$.

The range is the set of values that the function $f$ takes; since $f(x-2)$ is simply a value of $f$ for each input $x$, the range of the new function is the same as the range of the old function.

6
On

Key Point: For domain we need condition on $x$ and for range we need condition on $y$.

Given that domain of $f(x)$ is $-3 \leq x \leq 3$, it means whatever is written in place of '$?$' in $f(?)$ should lie between $-3$ and and $3$

Now if I write $x-2$ in place of '$?$', then I get

$$-3 \leq x-2 \leq3$$

But for domain we need condition of on x, hence add $2$ in inequality, which gives

$$-3+2 \leq x-2+2 \leq3+2$$

$$-1 \leq x\leq5$$ which is the required domain.

Is it clear now?