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Please give the answer

Please give the answer-example-1
User Quick Learner
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21 votes

Answer: See the attached image below for the filled in table.

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Step-by-step explanation:

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

The term "radicand" refers to the stuff under the square root.

We cannot have a negative number under the square root. Therefore, the radicand must be 0 or larger.

The first function must have
4x+6 \ge 0 which becomes
4x \ge -6 and leads to
x \ge -(6)/(4) aka
x \ge -(3)/(2)

So x = -3/2 is the smallest input allowed. Which is where the interval notation of
\left[-(3)/(2), \infty) comes from. It's the interval spanning from -3/2 (inclusive) to infinity. This represents the set of all possible x inputs of the first function.

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Follow this same idea for problem 2. The steps would be something like this:


-20x - 6 \ge 0\\\\-20x \ge 6\\\\x \le (6)/(-20)\\\\x \le -(3)/(10)\\\\

The inequality sign flips because we divided both sides by a negative number. That then leads to the interval notation of
(-\infty, -(3)/(10)\big]

The interval spans from negative infinity (exclusive) to -3/10 (inclusive).

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Problem 3 would have these steps


5x-16 \ge 0\\\\5x\ge 16\\\\x\ge (16)/(5)\\\\\big[(16)/(5), \infty)\\\\

No sign flip happens since we divided both sides by a positive number.

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Lastly, here are the steps for problem 4


20+6x \ge 0\\\\6x \ge -20\\\\x \ge -(20)/(6)\\\\x \ge -(10)/(3)\\\\\big[-(10)/(3), \infty)

Don't forget to use the square bracket to include the endpoints mentioned. We always use curved parenthesis for either infinity because we can't ever reach infinity. In a sense, we "approach" infinity.

Once again, all of this is summarized in the filled out table shown below (attached image). Feel free to ask any questions if they come to mind.

Please give the answer-example-1
User Radoslav Yordanov
by
2.9k points
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