Math professor battles himself in viral prank video

This one just didn't add up. Take a look.

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A math professor played a prank on his class at Biola University in Southern California on April Fool's Day, and the video quickly went viral.

Matthew Weathers was giving a lesson using a video of himself doing a trigonometry problem but then he solved the problem incorrectly, which he said was embarrassing. Weathers' video counterpart took offense to the comment, and what ensued was internet gold.

"I played a trick on my math class for April Fool's Day," he wrote on YouTube. "In this one, I'm showing a 'homework help' video that gets some trigonometry wrong. How embarrassing!"

Weathers is apparently known for his interactive lessons.