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Help me please!!!! I don’t get it

Help me please!!!! I don’t get it-example-1

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4 votes

Answers:

Domain: [ -1, 3 )

Range: ( -5, 4 ]

Be careful about the use of square brackets vs curved parenthesis.

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Step-by-step explanation:

The domain is the set of all allowed x values of a function. These are the inputs.

The furthest to the left we can go is x = -1. A closed endpoint is here meaning we include this as part of the domain. Unfortunately the other endpoint 3 is not included due to the open hole.

So x is between -1 and 3, including -1 but excluding 3

We can write that as the compound inequality
-1 \le \text{x} < 3 which then directly translates into the interval notation [ -1, 3 )

The square bracket includes the endpoint -1; in contrast, the curved parenthesis excludes 3

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The range deals with the output y values. It's the set of all possible outputs.

The lowest we can go is y = -5 but we can't actually reach it because of the open hole.

The highest we can go is y = 4 and we can reach this value.

Hence the range as a compound inequality is
-5 < \text{y} \le 4 and that leads to the interval notation ( -5, 4 ]

Once again, take note of the use of square brackets vs curved parenthesis. This time we're excluding the lower endpoint but including the higher endpoint.

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