theorem Lm220: :: FUZZY_8:22

for a, b, c, d being Real
for f being Function of REAL,REAL st b > 0 & c > 0 & d > 0 & d < b & ( for x being Real holds f . x = min (d,(max (0,(b - |.((b * (x - a)) / c).|)))) ) holds
f = d (#) (TrapezoidalFS ((a - c),(a + ((d - b) / (b / c))),(a + ((b - d) / (b / c))),(a + c)))