15-18 please help please... this is just our review... no need for solution please. answer directly only.... please... IN RETURN I WILL GIVE HELPFUL RATING DIRECTLY...

15. Evaluate J e* dx 1+e2x . A. 1/2 In(1 + e2x) + C C. 1/2 (1 + e2x)2+ C B. In(1 + e2x) + C D. arctan (ex) + C 16. Evaluate J dx Inx2 (In x)2-1 A. arcsec(In x) + C C. In (In x)2 - 1 +C B. (2/3) [(In x)2 - 1]3/2 + C D. arctan (In x) + C 17. Evaluate S x3+1 dx . x+2 A. x3 + x2 + 4x + 7 In (x+ 2)+C C. 3 - x2 +4x - 7 In(x + 2) + C B. x3 - - + 4x - In(x + 2) + C 3 D. -+ x2 + 4x -In(x + 2) + C 2x 18. Evaluate S dx . ex+1 A. 1/2 ex + In(ex + 1) + C C. In(e* + 1) + C B. ex - In(ex + 1) + C D. ex + In(e* + 1) + C