凤凰求蛊
#pnorm函数的使用形式：pnorm(p,mean=0,sd=1,lower.tail=TRUE,log.p=FALSE)#a.P(X>=2)pnorm(2,mean=2,sd=3,lower.tail=FALSE)#b.P(1<=X<7)pnorm(7,mean=2,sd=3,lower.tail=TRUE)-pnorm(1,mean=2,sd=3,lower.tail=TRUE)#c.P(-2.5<=X<-1)pnorm(-1,mean=2,sd=3,lower.tail=TRUE)-pnorm(-2.5,mean=2,sd=3,lower.tail=TRUE)#d.P(-3<=X-2<3)即P(-1<=X<5)pnorm(5,mean=2,sd=3,lower.tail=TRUE)-pnorm(-1,mean=2,sd=3,lower.tail=TRUE)向左转|向右转