Answer :
Use the rule of SINE(A+B)= SINACOSB+COSASINB
:. SIN(23pi/4+11pi/6)
-add both fractions
:. SIN(138pi/24+44pi/24)
-Simplify
:.SIN(182pi/24)
And simplify again the fraction
:.SIN(91pi/12) ---------Final answer
:. SIN(23pi/4+11pi/6)
-add both fractions
:. SIN(138pi/24+44pi/24)
-Simplify
:.SIN(182pi/24)
And simplify again the fraction
:.SIN(91pi/12) ---------Final answer