theorem :: INTEGR13:25

for A being non empty closed_interval Subset of REAL
for f being PartFunc of REAL,REAL
for Z being open Subset of REAL st A c= Z & f = ((id Z) (#) ((cos * ln) ^2)) ^ & Z c= dom (tan * ln) & Z = dom f & f | A is continuous holds
integral (f,A) = ((tan * ln) . (upper_bound A)) - ((tan * ln) . (lower_bound A))