1.

7. sec tan(3x) +C .

10.

ln .

13. sin Thus, the statement is false.

17. (xarctan ln arctan arctan x.

20. (ln |secx + tan secxtanx + sec secx + tanx)=secx.

23a. sin cos sin(2x)) + C.

23b. The statement follows from the fact that sinx on the interval

24. sinxcos sin cos cos sin Note that the last step follows from the trigonometric idenitity sin + cos = 1.