已经解决
<%
Randomize '初始化随机数生成器。
num1 = Int((9 * Rnd) + 1)
num2 = Int((9 * Rnd) + 1)
Response.write num1& " + "& num2 & " = "
session("num")=num1+num2%>
<input type="text" name="num" size="5" />
验证页面
if trim(request("num"))<>trim(session("num")) then
Response.write "您提交的验证答案错误!请返回重填!"
end if