Find the value of sin-1sin5π9cosπ9+cos5π9sinπ9

Find the value of $\sin^{- 1} (\sin \frac{5 π}{9} \cos \frac{π}{9} + \cos \frac{5 π}{9} \sin \frac{π}{9})$

Matching exercise

Match the items on the right to the items on the left.

step 1

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step 4