# Error in using "vary"

Hi,

I found a couple of errors in the command vary:

ex1:= \log(A);
vary(_, $A -> \delta{A}$);

,

ex2:= \ln(A);
vary(_, $A -> \delta{A}$);

, and

ex3:= \sin(A);
vary(_, $A -> \delta{A}$);

.
The first and second codes yields nothing. The last one causes the kernel crash. If I made just a stupid mistake in writing a code, please let me know. Thanks.

Best wishes, Yuta

P.S. Kasper, I posted the above in this forum just in case. Sorry if you already kept them in mind.