If the probability that the random variable X takes values x is given by P ( X =x)= k (x+1) 3^-x, x=0,1,2,3, …, where k is a constant, then P ( X ≥…

If the probability that the random variable X takes values $\displaystyle x$ is given by $\displaystyle \mathrm{P}(\mathrm{X}=x)=\mathrm{k}(x+1) 3^{-x}, x=0,1,2,3, \ldots$, where k is a constant, then $\displaystyle \mathrm{P}(\mathrm{X} \geq 2)$ is equal to