Identify the quadrant in which an angle of each given measure lies; 25⁰

Find the value of sin 105^o

Prove that \(\cos { \left( \pi +\theta \right) } =-\cos { \theta } \)

Find the principal value of \(sin^{ -1 }\left( \frac { 1 }{ \sqrt { 2 } } \right) \).

Find the principal value of cosec^-1(-1)

Find the principal value of sec^-1\(\left( -\sqrt { 2 } \right) \)

If tan² \(\theta\) = 1 - k², Show that sec \(\theta\) + tan³ \(\theta\) cosec \(\theta\) = (2 -k²)^3/2. Also, find the value of k for which this result holds

Express each of the following angles in radian measure
30⁰

Express each of the following angles in radian measure
135⁰