No. Meta elements can be completely ignored. You should send the appropriate cache control HTTP headers from your web server. The caching tutorial is a good place to start reading.
XHTML is case-sensitive and all element names and attribute names have to be lowercase. (Not necessarily attribute values, though.) Also, every element must be closed, and since meta elements can't have any content you can use the self-closing syntax (null end tag):
<meta http-equiv="Pragma" content="no-cache"/>