I can't work out problem in this way .Why ----it in some oth

I can't work out problem in this way .Why ____it in some other way?
A.not try doing
B.not try to do
选：A.not try doing
1).try to do:努力做某事,一般是不成功的,或者结果不明的.
2).try doing：尝试做某事.例如：
She tried to catch the bus ,but failed.
Her mother tried putting some salt in the soup.