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 writeEqn(){
   if (step == 0){
     string1 = "\\begin{array}{rcl}\\lim_{x\\rightarrow a}\\,f(x)\\,&=&\\lim_{x\\rightarrow a}\\,f(x)\\,-\\,f(a)\\,+\\,f(a)\\\\"
     string0 = string1+endString
     step = 1
   }
   else { if (step == 1){
     string2 = "&=&\\lim_{x\\rightarrow a}\\,[f(x)\\,-\\,f(a)]\\cdot\\frac{x-a}{x-a}\\,+\\,f(a)\\\\"
     string0 = string1+string2+endString
     step=2
   }
   else { if (step == 2) {
     string3 = "&=&\\lim_{x\\rightarrow a}\\,\\left[\\frac{f(x)\\,-\\,f(a)}{x-a}\\right]\\cdot[x-a]\\,+\\,f(a)\\\\"
     string0 = string1+string2+string3+endString
     step=3
   }
   else { if (step == 3) {
     string4 = "&=&\\lim_{x\\rightarrow a}\\,\\frac{f(x)\\,-\\,f(a)}{x-a}\\cdot\\lim_{x\\rightarrow a}\\,[x-a]\\,+\\,\\lim_{x\\rightarrow a}\\,f(a)\\\\"
     string0 = string1+string2+string3+string4+endString
     step=4
   }
   else { if (step == 4) {
     string5 = "&=&\\frac{df}{dx}(a)\\cdot 0+\\,f(a)\\\\"
     string0 = string1+string2+string3+string4+string5+endString     
     step=5
   }
   else { if (step == 5) {
     string6 = "&=&f(a)\\\\"
     string0 = string1+string2+string3+string4+string5+string6+endString     
     step=6
     document.derivative.Continue.value="Done!"
   }
   }}}}}
}