Teaching UP B.Ed (Paper 1 & 2) Mock Test 2025 Mathematics Trigonometry Inverse Trigonometric Functions
The principal value of the expression cos–1[cos (–680°)] is
1
\(\frac{2 \pi}{9}\)
2
\(\frac{−2 \pi}{9}\)
3
\(\frac{34 \pi}{9}\)
4
\(\frac{\pi}{9}\)