Column I, a) `int(e^(2x)-1)/(e^(2x)+1)dx` is equal to b) `int1/((e^x+e^(-x))^2)dx` is equal to c) `int(e^(-x))/(1+e^x)dx` is equal to d) `int1/(sqrt(1-e^(2x)))dx` is equal to COLUMN II p) `x-log[1+sqrt(1-e^(2x)]+c` q) `log(e^x+1)-x-e^(-x)+c` r) `log(e^(2x)+1)-x+c` s) `-1/(2(e^(2x)+1))+c`