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These curves occur often in the study of electronics. They form a good example of parametric curves.
This online exercise can either plot a Lissajous curve and ask you to recognize its equations among a list to choose from, or give a pair of equations and ask you to recognize the plotted Lissajous curve among a list to choose from.
Please take note that WIMS pages are interactively generated; they are not ordinary HTML files. They must be used interactively ONLINE. It is useless for you to gather them through a robot program.