Using the Horizontal Line Test

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How This Works

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The next tab (below this) is a panel which displays graphs of \( y=f(x) \) for various functions \( f\). For each graph, if the function is one-one, click anywhere in the plot except on the \(y\)-axis. If it is not, click on the \(y\)-axis at the \(y\)-intercept of an horizontal line which demonstrates that. You have three attempts for each graph.

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On the last tab, you'll find a display of the total number of questions you've finished (either answered correctly or used all three attempts without doing so), the total number of correct answers you've given, and the percent of finished problems which you've answered correctly. Try to keep answering questions until you've answered at least ten questions and the percent of correct answers is at least ninety.

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If you're having trouble recalling the definition of one-one-ness or how the horizontal line test works, follow the link below.

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