1 / | | -1 | ------ dx | cos(x) | / 0
Integral(-1/cos(x), (x, 0, 1))
/ | | -1 | ------ dx | cos(x) | /
-1 ------ cos(x)
cos(x)
-1 -cos(x)
------ = --------
cos(x) 2
cos (x) sin(a)^2 + cos(a)^2 = 1
2 2 cos (x) = 1 - sin (x)
-cos(x) -cos(x) -------- = ----------- 2 2 cos (x) 1 - sin (x)
u = sin(x)
/ | | -cos(x) | ----------- dx | 2 = | 1 - sin (x) | /
/ | | -cos(x) | ----------- dx | 2 = | 1 - sin (x) | /
/ | | -1 | ------ du | 2 | 1 - u | /
-1 -1 / 1 1 \
------ = ---*|----- + -----|
2 2 \1 - u 1 + u/
1 - u / /
| |
| 1 | 1
| ----- du | ----- du
/ | 1 + u | 1 - u
| | |
| -1 / / =
| ------ du = - ----------- - -----------
| 2 2 2
| 1 - u
|
/
= log(-1 + u)/2 - log(1 + u)/2
u = sin(x)
/ | | -1 log(-1 + sin(x)) log(1 + sin(x)) | ------ dx = ---------------- - --------------- + C0 | cos(x) 2 2 | /
/ | | -1 log(-1 + sin(x)) log(1 + sin(x)) | ------ dx = C + ---------------- - --------------- | cos(x) 2 2 | /
log(1 - sin(1)) log(1 + sin(1))
--------------- - ---------------
2 2
=
log(1 - sin(1)) log(1 + sin(1))
--------------- - ---------------
2 2
log(1 - sin(1))/2 - log(1 + sin(1))/2
Use the examples entering the upper and lower limits of integration.