12lntan(e−2x)+C\frac{1}{2} \ln \tan \left(e^{-2 x}\right)+C21lntan(e−2x)+C
12lnsec(2−2x)+C\frac{1}{2} \ln \sec \left(2^{-2 x}\right)+C21lnsec(2−2x)+C
−12lncos(e−2x)+C-\frac{1}{2} \ln \cos \left(e^{-2 x}\right)+C−21lncos(e−2x)+C
Both a and c \text { Both a and c } Both a and c
(No answer) \text { (No answer) } (No answer)