postest 1

#untuk p(X=4)
eks<-function(x,lambda=0.17){lambda*exp((-1)*lambda*x)}
eks(4,0.17)

## [1] 0.08612489

#untuk (X<=4)
cdfexp<-function(x,lambda=0.17){
  pdf<-function(t){
    lambda*exp(-lambda*t)
  }
  hasil<-integrate(pdf,lower=0,upper=x)
  return(hasil$value)
}
cdfexp(4,0.17)

## [1] 0.493383

norm<-function(x,miu,sigma){1/(sigma*sqrt(2*pi))*exp(-1/2*((x-miu)/sigma)^2)}
norm(4,5,1)

## [1] 0.2419707

dnorm(4,mean=5,sd=1)

## [1] 0.2419707