The value of \sin ^{-1} (\cos \frac{3 \pi}{5}) is

CBSE Class 12 Math 2020 Outside Delhi Set 1 Solved Paper

Section - A

Question numbers

\bo {1}

\bo {10}

are multiple choice questions of

\bo {1}

mark each. Select the correct option :

Question : 1 of 36

Marks: +1, -0

The value of

sin \;^{-1} (\cos \;{3 π}/{5})

Solution:

sin \;^{-1} (\cos \;{33 π}/{5}) = sin \;^{-1} (\cos (6 π+\;{3 π}/{5}) )

= sin \;^{-1} (\cos (\;{3 π}/{5}) )

sin \;^{-1} (\cos (\;{π}/{2}+\;{π}/{10}) )

= sin \;^{-1} (- sin \; (\;{π}/{10}) )

∴ sin \;^{-1} (\cos \;{33 π}/{5}) =\;{-π}/{10}

Go to Question:

Next Question