Strange that it would get published like that. It makes me guess that the site is created "automatically". So the source data is probably in a database, and it gets created automatically and the results are not checked.
]]>In contrast, mathworld has Eric Weisstein, Wikipedia has everybody, Cut the Knot has Alexander Bogolmony, and so on.
And what is a "Amplitudenbspnbspof"?: http://libraryofmath.com/Trigonometry_Example_Amplitudenbspnbspof_Sine_and_Cosine.html
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