解：原式=（1-1/2-1/3-1/4-1/5）*（1/2+1/3+1/4+1/5）+1/6*（1-1/2-1/3-1/4-1/5）-（1-1/2-1/3-1/4-1/5）*（1/2+1/3+1/4+1/5）+1/6*（1/2+1/3+1/4+1/5）=1/6*（1-1/2-1/3-1/4-1/5+1/2+1/3+1/4+1/5）=1/6*1=1/6希望对你有帮助
