title: need to optimize specific function in order to have best fitted curve
body: <p>I'm looking for best fitted curve that will match with a specific formula. The parameters A and B need to be optimize</p>
  
  <pre><code># X and Y are my datasets Y depend of X
  X=c(73,33,201,90,1513,1312,1044,929,836,657,104,22)
  Y=c(2.89,6.11,3.57,4.03,0.16,0.00,1.41,0.00,2.13,6.16,2.85,5.08)        
  
  # X and Y plot give us
  plot(X,Y, main="Y function of X",pch=6,xlab="X", ylab="Y",col='black')        
  
  
  #Type of curve that I need
  curve(0.07*90*(1-(x/(x+exp(5-0.001*x)))), add = T,col="blue",lw=3,lty=2)
  
  
  #I want therefore to optimize the parameters A and B in order to have the best fitted curve according to this formula that fit better with my data 
  curve(0.07*90*(1-(x/(x+exp(B+A*x)))), add = T, col="blue",lw=3,lty=2)         
  
  # Please help `enter code here`
  </code></pre>