Lösungen zu Folgen
(Dittrich / Lehrerfortbildung CAS 1997/98 /casFort/LoeAb3)

restart;
f:=n->(1+1/n)^n;
Aha:=f(n+1)-f(n);
normal(Aha);
simplify(");


restart;
f:=n->(n)^(1/n);
Differ:=f(n+1)-f(n);
simplify(Differ);
expand(Differ);
solve(Differ<0,n); Error, (in solve/ineqs)  
unable to determine sign of expression
Quot:=(f(n+1)/f(n));
expand(Quot);
simplify(Quot);
solve(Quot>1,n); Error, (in solve/ineqs)  
unable to determine sign of expression


restart;
f:=n->1/sqrt(n+1)+1/sqrt(n);
Differ:=f(n+1)-f(n);


restart;
f:=n->3^n/n^3;
Differ:=f(n+1)-f(n);
simplify(Differ);
Z:=numer(Differ);
collect(Z,n);
factor(Z);
A1:=simplify(Z/3^n);
Loesung:=solve(A1<0,n);
evalf(Loesung);

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Aufbereitet fürs Internet: Roland Bernert