<HTML ><HEAD ><TITLE >sqrt</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.7"><LINK REL="HOME" TITLE="PHP Manual" HREF="index.html"><LINK REL="UP" TITLE="Mathematical Functions" HREF="ref.math.html"><LINK REL="PREVIOUS" TITLE="sinh" HREF="function.sinh.html"><LINK REL="NEXT" TITLE="srand" HREF="function.srand.html"><META HTTP-EQUIV="Content-type" CONTENT="text/html; charset=ISO-8859-1"></HEAD ><BODY CLASS="refentry" BGCOLOR="#FFFFFF" TEXT="#000000" LINK="#0000FF" VLINK="#840084" ALINK="#0000FF" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >PHP Manual</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="function.sinh.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="function.srand.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="function.sqrt" ></A >sqrt</H1 ><DIV CLASS="refnamediv" ><A NAME="AEN45275" ></A ><P > (PHP 3, PHP 4 )</P >sqrt -- Square root</DIV ><DIV CLASS="refsect1" ><A NAME="AEN45278" ></A ><H2 >Description</H2 >float <B CLASS="methodname" >sqrt</B > ( float arg)<BR ></BR ><P > Returns the square root of <TT CLASS="parameter" ><I >arg</I ></TT >. </P ><P > <DIV CLASS="informalexample" ><A NAME="AEN45289" ></A ><P ></P ><TABLE BORDER="0" BGCOLOR="#E0E0E0" CELLPADDING="5" ><TR ><TD ><PRE CLASS="programlisting" ><?php // Precision depends on your precision directive echo sqrt(9); // 3 echo sqrt(10); // 3.16227766 ... ?></PRE ></TD ></TR ></TABLE ><P ></P ></DIV > </P ><P > See also <A HREF="function.pow.html" ><B CLASS="function" >pow()</B ></A >. </P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="function.sinh.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="function.srand.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >sinh</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="ref.math.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >srand</TD ></TR ></TABLE ></DIV ></BODY ></HTML >