**TI92P*maince.RimpdiffZL(f,x,y) Func This function computes dy/dx from the implicit relation f(x,y)=0. Local replace,f,g,d Define replace(str1,str2,str3)=Func This function replaces every occurence of str2 in str1 with str3. Local l1,l2,n,leftstr,str1 dim(str2)l2 ""leftstr inString(str1,str2)n While n0 dim(str1)l1 leftstr&left(str1,n-1)&str3leftstr right(str1,l1-n-l2+1)str1 inString(str1,str2)n EndWhile Return leftstr&str1 EndFunc Find df/dx assuming that y=g(x). (f|y=g(x),x)d Replace all occurences of (g(x),x) and g(x) with and y respectively. string(d)d replace(d,"(g("&string(x)&"),"&string(x)&")","")d replace(d,"g("&string(x)&")",string(y))d expr(d)d Solve for dy/dx d|=0f d+f|=1g Return f ./ g EndFuncBr