Let x be a random variable with mean μ and standard deviation σ. then the skew of x can be defined as follows: x − μ 3 e[x3] − 3μσ2 − μ3 skew(x) = e σ = σ3 show that the exponential distribution is always skewed right by showing that for x ∼ exponential(λ) the skew is always positive regardless of λ.