The correct option is A 0
π/2∫0[cos(2018πsin2x)+cos(1009πsinx)]dx
Let I1=π/2∫0cos(2018πsin2x)dx
and I2=π/2∫0cos(1009πsinx)dx
Now, I1=π/2∫0cos(1009π(1−cos2x))dx
⇒I1=−π/2∫0cos(1009πcos2x)dx⇒I1=−2π/4∫0cos(1009πcos2x)dx
Assuming 2x=t⇒2dx=dt
⇒I1=−π/2∫0cos(1009πcost)dt
Putting t→π2−t, we get
I1=−I2∴I1+I2=0