We're doing differential operators in my Differential Equations class right now, and our professor assigned the following problem to us:(adsbygoogle = window.adsbygoogle || []).push({});

(D-x)(D+x)

Which inevitably gives us the following terms as part of the final answer: Dx-xD

The answer in the book tells me that Dx-xD = 1, and some preliminary research has told me that this is true. What I couldn't find was the why. Why, or how, does Dx-xD result in 1? And does -Dx+xD = -1?

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# Homework Help: Differential Operators

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