orm onsubmit="return false;">
	Polynomial degree:
	<button type="button" onclick="dec('app_degree')">-</button>
	<input type="text" id="app_degree_input" value="2" onchange="change_app_degree();">
	<button type="button" onclick="inc('app_degree')">+</button>
	<br>
	</form>
	<canvas id="approximation_canvas" width=640 height=640></canvas>
	<div style="text-align:center; padding-bottom:12pt;">
		<input type="radio" name="approx" id="a_1" value="Add" /><label for="a_1">Add a point;</label> &nbsp;
		<input type