# Content error: Exercice D.2.1

**URL:** <https://discuss.pennylane.ai/t/content-error-exercice-d-2-1/7661>\
**Category:** Codebook\
**Created:** [November 26, 2024, 1:34pm UTC](https://discuss.pennylane.ai/t/content-error-exercice-d-2-1/7661 "2024-11-26T13:34:05Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![quantumel](https://avatars.discourse-cdn.com/v4/letter/q/7ea924/32.png) [@quantumel](https://discuss.pennylane.ai/u/quantumel)\
**Post date:** [November 26, 2024, 1:34pm UTC](https://discuss.pennylane.ai/t/content-error-exercice-d-2-1/7661/1 "2024-11-26T13:34:05Z")

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Hi,

just inform you sign - error instead of + in the exercices D.2.1

Best regards

 ![Signe-Error-ExerciceD.2.1](https://canada1.discourse-cdn.com/flex012/uploads/pennylane/original/2X/e/ee623c2fa849def5a616166fd21d54445f2b760f.jpeg)

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**Author:** ![CatalinaAlbornoz](https://yyz2.discourse-cdn.com/flex012/user_avatar/discuss.pennylane.ai/catalinaalbornoz/32/1196_2.png) [@CatalinaAlbornoz](https://discuss.pennylane.ai/u/CatalinaAlbornoz)\
**Post date:** [November 27, 2024, 4:36pm UTC](https://discuss.pennylane.ai/t/content-error-exercice-d-2-1/7661/2 "2024-11-27T16:36:28Z")

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Hi @quantumel , great catch! Thank you for pointing this out 🙌