function chkdiv(divid){
	var chkid=document.getElementById(divid);
	if(chkid != null){return true; }
	else {return false; }	
}
if (chkdiv('fy')){
	document.getElementById('fy').innerHTML='上一篇：<a href="/News/2015-7/112022">【方法技巧】双曲线的渐近线的“垂径定理” </a>  下一篇：<a href="/News/2015-7/112024">高中数学精选题（68）均值不等式与裂项求和 </a> ';
}