var step=0
var string1 = "Test"
var string2
var string3
var string4
var string5
var string6
var string7
var endString ="\\end{array}"
var string0 = string1+endString

function writeEqn(){
   if (step == 0){
     string1 = "\\begin{array}{rcl}\\frac{d}{dx}\\,\\tan(x)&=&\\,\\frac{d}{dx}\\,\\frac{\\sin(x)}{\\cos(x)}\\\\"
     string0 = string1+endString
     step = 1
   }
   else { if (step == 1) {
     string2 = "&=&\\,\\frac{\\cos(x)\\,\\frac{d\\,\\sin(x)}{dx}\\,-\\,\\sin(x)\\,\\frac{d\\,\\cos(x)}{dx}}{\\cos^2(x)}\\\\"
     string0 = string1+string2+endString
     step=2
   }
   else { if (step == 2) {
     string3 = "&=&\\,\\frac{\\cos(x)\\cdot\\cos(x)\\,-\\,\\sin(x)\\cdot-\\sin(x)}{\\cos^2(x)}\\\\"
     string0 = string1+string2+string3+endString
     step=3
   }
   else { if (step == 3) {
     string4 = "&=&\\,\\frac{\\cos^2(x)\\,+\\,\\sin^2(x)}{\\cos^2(x)}\\\\"
     string0 = string1+string2+string3+string4+endString
     step=4
   }
   else { if (step == 4) {
     string5 = "&=&\\,\\frac{1}{\\cos^2(x)}\\\\"
     string0 = string1+string2+string3+string4+string5+endString
     step=5
   }   
   else { if (step == 5) {
     string6 = "&=&\\,\\sec^2(x)\\\\"
     string0 = string1+string2+string3+string4+string5+string6+endString     
     step=6
     document.derivative.Continue.value="Done!"
   }
   }}}}}
}