elieve和trust相信不疑的意思.但词义用法有细微区别.
believe in sth ：1、to be certain that something exists
如：Do you believe in ghosts?（意思是有没有鬼魂）
2、to be confident that something is effective and right
如：They don't believe in living together before marriage.
He believes in saying what he thinks.
believe in sb ：to trust someone because you think that they can do something well or that they are a good person
如：Gradually,since her divorce,she's beginning to believe in herself again（意思是她觉得她能不靠他人了）
trust：to have belief or confidence in the honesty,goodness,skill or safety of a person,organization or thing
如：My sister warned me not to trust him.（意思是他是不是可信任的人）
Trust me - I know about these things.