`sin 163^0cos 347^0+s in 73^0s in 167^0=` `1//2` b. `1` c. `0` d. none of these

Explanation

`sin 163^{circ} cos 347^{circ}+sin 73^{circ} sin 167^{circ}`


`=sin (180^{circ}-17^{circ}) cos (360^{circ}-13^{circ})+sin (90^{circ}-17^{circ}) sin (180^{circ}-13^{circ})`


`=sin 17^{circ} cos 13^{circ}+cos 17^{circ} sin 13^{circ}`


`=sin (17^{circ}+13^{circ})[sin (A+B)=sin A cos B+sin B cos A]`


`=sin 30^{circ}`


`=frac{1}{2}`