I have been copying from class text to a blade on Sharelatex, and it seems the teachers use the symbol (\!) a lot.
\sin\!\left(x\right)=\frac{-1}{\sqrt{2}}
\cos\!\left(\frac{\pi }{12}\right)
Why do they need to use the symbol for exclamation mark(!) ?
\leftand\rightare totally unnecessary in the first example and will give inferior results. https://tex.stackexchange.com/questions/74353/what-commands-are-there-for-horizontal-spacing – Au101 May 12 '18 at 05:35\!not!, see https://tex.stackexchange.com/questions/9091/what-is-the-right-way-to-use-the-spacing-command/9255 – DG' May 12 '18 at 06:47texdoc mleftright. – GuM May 12 '18 at 08:00