c) S 1 = f ( a ) − f ( b ) , S 2 = f ( a ) − f ( c ) .

c) \({S_1} = \int_a^b {\left| {{f^\prime }(x)} \right|} dx = \int_a^b {{f^\prime }} (x)dx = f(b) - f(a).\)

\({S_2} = \int_b^c {\left| {{f^\prime }(x)} \right|} dx = \int_b^c  -  {f^\prime }(x)dx = f(b) - f(c).\)

=> Sai