Reconstructing your code a bit:
function activateMaxMin(elemButton,elemMax,elemBox)
{
var isclass = elemButton.attr('class');
if (isclass == "max")
{
elemMax.attr("src","<%=request.getContextPath()%>/img/Minimize.png");
elemButton.removeClass('max');
}
else{
elemButton.addClass('max');
elemMax.attr("src","<%=request.getContextPath()%>/img/Maximize.png");
}
elemBox.slideToggle();
}
$("#button").click(function(){
activateMaxMin($(this),$("#max"),$("#box"));
});
In case there is another button like this, use:
$("#button1").click(function(){
activateMaxMin($(this),$("#max1"),$("#box1"));
});
Of course, it could have been done in more efficient way, but that would need rewriting your code entirely.