# 1.a)
x <- c(1,2,3)
y <- c(6,5,4)

x*2
# 2 4 6
x*y
# 6 10 12
x[1]*y[2]
# 5
1/x
# 1 0.5 0.33333333
(1:10) * x[2]
# 2 4 6 8 10 12 14 16 18 20
rep(c(1,1,2), times = 2)
# 1 1 2 1 1 2

# 1.b)
# Arroja un error

# 2.a)
tratamiento <- c(rep("A", times = 20), rep("B", times = 18), rep("C", times = 22))
tratamiento

# 2.b)
j <- c(seq(5,100,5))
j
j[1]+j[8]

# 3.a)
q <- c(3,0,1,6)
r <- c(1,0,2,4)
q%*%r
sum(q*r)

# 3.b)
a <- rbind(q,r)
matrix(c(q,r),2,4,byrow = TRUE)
a

# 3.c)
b <- cbind(q,r)
b

# 3.d)
a%*%b

# 3.e)
solve(a%*%b)

# 3.f)
a
a[,1] = rep(1, 2)
a

# 3.g)
b
b[,2]

# 4)

sum(rep(1:100)^2)

# 5.a)

rownames(mtcars)[mtcars$gear==4]

# 5.b)
rownames(mtcars)[mtcars$disp > 150 & mtcars$mpg > 20]

rownames(mtcars[mtcars$disp > 150 & mtcars$mpg > 20,])

# 5.c)
rownames(mtcars[mtcars$gear == 4 & mtcars$am == 1,])

# 5.d)
mean(mtcars[mtcars$carb == 2,]$mpg)
mean(mtcars$mpg[mtcars$carb == 2])