Question: $\int _ { \pi / 4 } ^ { 3 \pi / 4 } \frac { d x } { 1 + \cos x }$ is equal to -...

Question

$\int _ { \pi / 4 } ^ { 3 \pi / 4 } \frac { d x } { 1 + \cos x }$ is equal to -

Answer 1

I = =

(Property 8)

=

\ 2I = $\int _ { \pi / 4 } ^ { 3 \pi / 4 } \left( \frac { 1 } { 1 + \cos x } + \frac { 1 } { 1 - \cos x } \right)$

dx = dx

= $- \left. 2 \cot \mathrm { x } \right| _ { \pi / 4 } ^ { 3 \pi / 4 }$ = 4. Hence I = 2.

Question: \(\int _ { \pi / 4 } ^ { 3 \pi / 4 } \frac { d x } { 1 + \cos x }\) is equal to -...