#Cau 1 a
setwd("D:/Thực hành XSTK/Bai TH04-05/Data cho cac bai thuc hanh")
data=read.csv('volume.csv',header=)
x=(data['machine1'])
y=(data['machine2'])
n1=unlist(x)
n2=unlist(y)
t.test(n1,n2,alternative='two.sided',var.equal=FALSE,conf.level=0.95)

#Cau 1 d

test.leq.oneside=function(x, y, a , a1 ,a2 ,alpha)
{
	Sx=var(x)
	Sy=var(y)
	n=length(x)
	m=length(y)
	Sp=((n-1)*Sx^2+(m-1)*Sy^2)/(n+m-2)
	Mx=mean(x)
	My=mean(y)

	T0 = (Mx-My)/sqrt(Sx^2/n+Sy^2/m)
	df = ((Sx^2/n+Sy^2/m)^2)/((Sx^2)^2/(n-1)+(Sy^2)^2/(m-1))
	t = pt(1-alpha/2,df)
	p_value = 2* pt(abs(T0), df)
	if(abs(T0)>t)
	print("Bac Bo")
	else
	print("Khong du dieu kien")
	print(p_value)
}
test.leq.oneside(n1,n2,0,0.2,0.3,0.05)