Add basic HTML tags

Getting the following ERROR in the Firefox: Tools -> Web Developer -> Web Console (CTRL+SHIFT+K)

[11:16:14.305] The character encoding of the HTML document was not declared. The document will render with garbled text in some browser configurations if the document contains characters from outside the US-ASCII range. The character encoding of the page must be declared in the document or in the transfer protocol. @ file:///home/satishg/Documents/math1.html