√(log(2) 5 + 16 log(5) 2 - 8)*log(5) 2) + 4 log(5) 12.5 = √(log(2) 5 * log(5) 2 + 16 log(5) 2 * log(5) 2 - 8*log(5) 2) + 4 log(5) 12.5 = { log(a) b * log(b) a =1} =
= √(1 + 4² * log² (5) 2 - 8*log(5) 2) + 4 log(5) 12.5 = √(1 - 4 log(5) 2)² + 4 log(5) 12.5 = { 4 log(5) 2 > 1} = 4 log(5) 2 - 1 + 4 log(5) 12.5 = 4 (log(5) 2 + log(5) 12.5) - 1 = { log(a) b + log(a) c = log(a) bc} = 4 log(5) 25 - 1 = 8 - 1 = 7