แทรก phpใน JavaScript แล้ว มันรันไม่ได้ พี่ๆช่วยเช็คให้ทีครับ ผิดตรงไหน

function showform(){
		<?php
		if (isset($_REQUEST["page"])) 
			echo"{";
			$page = $_REQUEST["page"];
			if($page == "1")
			echo"{";
		?>
			document.getElementById("D1").style.display = "none";
            document.getElementById("D2").style.display = "none";
			document.getElementById("D13").style.display = "none";
			document.getElementById("D14").style.display = "none";
			document.getElementById("D15").style.display = "block";

			document.getElementById("D3").style.display = "block";
            document.getElementById("D4").style.display = "none";
			document.getElementById("D5").style.display = "block";
            document.getElementById("D6").style.display = "none";
			document.getElementById("D7").style.display = "block";
            document.getElementById("D8").style.display = "none";
			document.getElementById("D9").style.display = "block";
            document.getElementById("D10").style.display = "none";
			document.getElementById("D11").style.display = "none";
            document.getElementById("D12").style.display = "block";
		<?php echo"}";
			  echo"}";
		?>
		}