<center>
<form>
<table bgcolor="#C0C0C0" cellspacing=2 cellpadding=2 border=3>
<tr>
<td>
<b>
<h3>
<input name="a" size="3">
X²+
<input name="b" size="3">
X +
<input name="c" size="3">
<br>
<input type="button" value="x-top" name="x-top" onclick="xtop(this.form)">
<input type="button" value="y-top" name="y-top" onclick="ytop(this.form)">
<input type="button" value="crd" name="crd" onclick="doCoord(this.form)">
<input type="button" value="disc." name="D" onclick="disc(this.form)">
<br>
<input type="button" value="0-points" name="zeroes"
onclick="zeroes1(this.form);zeroes2(this.form)">
<input type="button" onclick="xtop(this.form);ytop(this.form);doCoord(this.form);
disc(this.form);zeroes1(this.form);zeroes2(this.form)" value="do all">
<input type="button" name="pics" value="show e.g." onClick="if(form.a.value>0 && form.o.value>0)move_in('p','../zh/images/p2.gif');
if (form.a.value<0 && form.o.value>0)move_in('p','../zh/images/p3.gif');
if(form.a.value>0 && form.o.value==0) move_in('p','../zh/images/p4.gif');
if(form.a.value<0 && form.o.value==0) move_in('p','../zh/images/p5.gif');
if(form.a.value>0 && form.o.value<0) move_in('p','../zh/images/p6.gif');
if(form.a.value<0 && form.o.value<0) move_in('p','../zh/images/p7.gif')">
<br>
<input type="text" name="u" size="8">
x-top<br>
<input type="text" name="u2" size="8">
y-top<br>
<input type="text" size="8" name="co" onmouseover="form.rem.value=form.co.value">
Coord.<br>
<input type="text" size="8" name="o">
Discriminant<br>
<input type="text" size="8" name="n">
neg zero pt.<br>
<input type="text" size="8" name="n2">
pos zero pt.
<input type="hidden" value="" name="rem">
<br>
<input type="reset" value="reset">
<br>
</h3>
</b> </td>
<td>
<img src="p1.gif" width=200 name="p" height=200 border=0 alt="">
</td>
</tr>
</table>
</form>
</center>