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Write a rule for the piecewise function.

Please help as soon as possible!!! Only serious answers

Write a rule for the piecewise function. Please help as soon as possible!!! Only serious-example-1
User Subway
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1 Answer

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19 votes

The blue line has slope +1 and passes through the point (-3, 0). Using the point-slope formula, its equation would be

y - 0 = 1 (x - (-3))

or

y = x + 3

and so f(x) is defined by x + 3 for x ≤ 0.

The red line is horizontal for 0 < x < 3, so f(x) has a constant value of 1 for this interval. We use a strict inequality because the points (0, 1) and (3, 1) are unfilled circles.

The black (?) line has slope -1 and passes through (3, 0), so its equation is

y - 0 = -1 (x - 3)

or

y = -x + 3

so f(x) is defined by -x + 3 for x ≥ 3.

Putting everything together,


f(x) = \begin{cases}x+3&amp;\text{if }x\le0\\1&amp;\text{if }0<x<3\\-x+3&amp;\text{if }x\ge3\end{cases}

User Tim Van Oostrom
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