0ΠZ41SIN XB) I =COS X D (COS X) = − LN |COS X|| 0Π4 = 12 LN 2

4 .

0

π

Z

4

1

sin x

b) I =

cos x d (cos x) = − ln |cos x|| 0

π4

= 1

2 ln 2.

cos x dx = −

Z

22

sin x − 2sin 3 x

cos 4 x cos xdx =

d (sin x) =

1 − sin 2 x 2

= 6

c) I =

3 + sin 5 x

5