Question

5. Determine the value ofsin 230 cos 670 +cos 230 Sin 670.
6. Find the value of if 2 sin30 =V3.
7. IfPand Q are acute angles such that sine P- cos Q=0. Show​

Answer 1

Step-by-step explanation:

sin 230° cos 670° + cos 230° sin 670°

[ sin A cos B + cos A sin B = sin (A + B) ]

=> sin ( 230° + 670° ) = sin 900°

=> sin (720° + 180°)

[ sin 5 π , sin nπ => 1 if n is even and -1 if n is odd and 0 if n = 0 ]

=> sin 180°

=> -1