# Equation (6.47) is an approximate formula for the average probab

# Equation (6.47) is an approximate formula for the average probab

Equation (6.47) is an approximate formula for the average probability of symbol error for coherent Mary P5K. This formula was derived using the union bound in light of the signal-space diagram of Figure b. Given that message point rn1 was transmitted, show that the approximate formula of Equation (6.47) may be derived directly from Figureb.