var aVar = 1
var bVar = 1
var cVar = 1
var step = 0
var poly
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)\\,=\\,\\frac{1}{"+bVar+"+"+cVar+"\\cdot x}\\;\\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{\\frac{1}{"+bVar+"+"+cVar+"\\cdot("+aVar+"+h)}-\\frac{1}{"+bVar+"+"+cVar+"\\cdot"+aVar+"}}{h}\\\\" 
     string0 = string1+string2+endString
     step=2
   }
   else { if (step == 2) {
     aTmp=bVar+cVar*aVar
     string3 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{\\frac{1}{"+aTmp+"+"+cVar+"\\cdot h}-\\frac{1}{"+aTmp+"}}{h}\\\\"
     string0 = string1+string2+string3+endString
     step=3
   }
   else { if (step == 3) {
     aTmp=bVar+cVar*aVar
     string4 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{\\frac{"+aTmp+"-\\;["+aTmp+"+"+cVar+"\\cdot h]}{["+aTmp+"+"+cVar+"\\cdot h]\\cdot"+aTmp+"}}{h}\\\\" 
     string0 = string1+string2+string3+string4+endString
     step=4
   }
   else { if (step == 4) {
     aTmp=bVar+cVar*aVar
     string5 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{1}{h}\\cdot\\frac{-\\;"+cVar+"\\cdot h}{["+aTmp+"+"+cVar+"\\cdot h]\\cdot"+aTmp+"}\\\\"
     string0 = string1+string2+string3+string4+string5+endString     
     step=5
   }
   else { if (step == 5) {
     string6 = "&=&\\lim_{h\\rightarrow 0}\\,\\frac{-\\;"+cVar+"}{["+aTmp+"+"+cVar+"\\cdot h]\\cdot"+aTmp+"}"
     string0 = string1+string2+string3+string4+string5+string6+endString     
     step=6
   }
   else { if (step == 6) {
     string7 = "\\,=\\,\\frac{-\\;"+cVar+"}{"+aTmp+"^2}\\\\"
     string0 = string1+string2+string3+string4+string5+string6+string7+endString     
     step=7
     document.derivative.Continue.value="Done!"
   }
   }}}}}}
}