var aVar = 7
var bVar = 9
var cVar = 3
var step = 0
var poly = "f(x)=x^2+9x+3\\;\\mbox{ at } x=7"
var string1 = "Test"
var string2
var string3
var string4
var string5
var string6
var endString ="\\end{array}"
var string0 = string1+endString

function writeNewEqn(){
   with(Math){
     aVar = round(10*random()+1)
     bVar = round(10*random()+1)
     cVar = round(10*random()+1)
   }
   poly="f(x)=x^2+"+bVar+"x+"+cVar+"\\; \\mbox{ at } x ="+aVar
   step=0
}
function writeEqn(){
   if (step == 0){
     string1 = "\\begin{array}{rcl}\\lim_{h\\rightarrow 0}\\,\\frac{f("+aVar+"+h)\\,-\\,f("+aVar+")}{h}\\,&=&"
     string0 = string1+endString
     step = 1
   }
   else { if (step == 1){
     string2 = "\\lim_{h\\rightarrow 0}\\,\\frac{[("+aVar+"+h)^2+"+bVar+"("+aVar+"+h)+"+cVar+"]-["+aVar+"^2+"+bVar+"\\cdot"+aVar+"+"+cVar+"]}{h}\\\\" 
     string0 = string1+string2+endString
     step=2
   }
   else { if (step == 2) {
     aTmp=aVar*aVar
     bTmp=2*aVar
     cTmp=aVar*bVar
     dTmp=aVar*aVar+cTmp+cVar
     string3 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{[("+aTmp+"+"+bTmp+"h+h^2)+("+cTmp+"+"+bVar+"h)+"+cVar+"]-"+dTmp+"}{h}\\\\"
     string0 = string1+string2+string3+endString
     step=3
   }
   else { if (step == 3) {
     aTmp=2*aVar+bVar
     string4 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{h^2+"+aTmp+"h}{h}\\\\"
     string0 = string1+string2+string3+string4+endString
     step=4
   }
   else { if (step == 4) {
     string5 = "&=&\\lim_{h\\rightarrow 0}\\,h+"+aTmp+"\\\\"
     string0 = string1+string2+string3+string4+string5+endString     
     step=5
   }
   else { if (step == 5) {
     string6 = "&=&"+aTmp+"\\\\"
     string0 = string1+string2+string3+string4+string5+string6+endString     
     step=6
     document.derivative.Continue.value="Done!"
   }
   }}}}}
}