ShmoopTube

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Here's your shmoop du jour...

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Which equation is expressed in the following graph?

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And here are your options...

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Don't worry, you're not seeing things. The cosine graph really is lined up incorrectly

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with the x-axis values. But... what does this mean?

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Well the graph was shifted a bit to the right

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or left. ...which means that there is an addition or

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subtraction to the x in the parentheses of the cosine function, which is expressed in

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options A and D. Now we just have to figure out if it is plus 2 or minus 2.

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A plus two would mean a shift to the left, while a minus two would mean a shift to the

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right. If we were to draw a normal cosine graph on the same set of axis, it would be

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a bit to the right of the one shown. That means that the graph here was shifted

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to the left, yielding a result of cos(x + 2).

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This is represented in choice A. Which turns out to be our answer!

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