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MCQ (Multiple Choice Question):

What are the positive and negative intervals for the function f(x) = x + 2?

A) Positive: (-2, [infinity]), Negative: (-[infinity], -2)
B) Positive: (-[infinity], -2), Negative: (-2, [infinity])
C) Positive: (0, [infinity]), Negative: (-[infinity], 0)
D) Positive: (-[infinity], 0), Negative: (0, [infinity])

User Dayquan
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1 Answer

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Final answer:

To find where the function f(x) = x + 2 is positive or negative, inequalities x + 2 > 0 and x + 2 < 0 are solved, yielding positive interval (-2, ∞) and negative interval (-∞, -2), respectively.

The correct answer to the question is A) Positive: (-2, ∞), Negative: (-∞, -2).

Step-by-step explanation:

The question is about determining the positive and negative intervals for the function f(x) = x + 2.

To find out where the function is positive, we set f(x) to be greater than zero.

f(x) > 0 leads to x + 2 > 0. Solving this inequality, we get x > -2.

Hence, the function is positive for all x values greater than -2, which is the interval (-2, ∞).

Similarly, finding where the function is negative, we set f(x) to be less than zero: f(x) < 0.

This inequality translates to x + 2 < 0, solving which we get x < -2.

Therefore, the function is negative for all x values less than -2, corresponding to the interval (-∞, -2).

The correct answer for the student's MCQ is option A) Positive: (-2, ∞), Negative: (-∞, -2).

User SethGunnells
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