Question

is equal to

• A. a
• B. a/2
• C. 2a
• D. 0

Answer 1

Answer: (A)

a

Answer 2

$I = \int _ { 0 } ^ { 2 a } \frac { f ( x ) } { f ( x ) + f ( 2 a - x ) } d x = \int _ { 0 } ^ { 2 a } \frac { f ( 2 a - x ) } { f ( 2 a - x ) + f ( x ) } d x$ $2 I = \int _ { 0 } ^ { 2 a } \frac { f ( x ) + f ( 2 a - x ) } { f ( x ) + f ( 2 a - x ) } d x = \int _ { 0 } ^ { 2 a } d x = [ x ] _ { 0 } ^ { 2 a } = 2 a$ $\therefore I = a$.