L Cauchy
(1789-1857)
360
MATHEMATICS
Fig  8 2
This area is called the elementary area which is located at an arbitrary position
within the region which is specified by some value of x between a and b We can think
of the total area A of the region between x-axis, ordinates x = a, x = b and the curve
y = f (x) as the result of adding up the elementary areas of thin strips across the region
PQRSP