For example, when \(x=2\), we see in the expression on the right-hand side of Equation \ref{binomexample} that "2" appears in the binomial coefficient \(\binom{3}{2}\), which gives the number of outco...For example, when \(x=2\), we see in the expression on the right-hand side of Equation \ref{binomexample} that "2" appears in the binomial coefficient \(\binom{3}{2}\), which gives the number of outcomes resulting in the random variable equaling 2, and "2" also appears in the exponent on the first \(0.5\), which gives the probability of two heads occurring.
