IJM98

IJM98, you are invited to the Teahouse!

Hi IJM98! Thanks for contributing to Wikipedia. Be our guest at the Teahouse! The Teahouse is a friendly space where new editors can ask questions about contributing to Wikipedia and get help from experienced editors like Doctree (talk). Visit the Teahouse We hope to see you there! Delivered by HostBot on behalf of the Teahouse hosts 20:03, 11 August 2017 (UTC)

Please be more careful

Hi there, please be more careful when removing content as you did here. That edit had the following two problems: (1) some of the terms ("product rule" and "chain rule") were indeed mentioned in the original source, and (2) you destroyed the pointer to the image. So next time, before you remove sourced content, please verify the source first, and before you hit Save changes, please use the Show preview function to verify. Thanks and happy editing. - DVdm (talk) 08:39, 31 August 2017 (UTC)