gaokao 2020 Q5

gaokao · China · national-III-arts 5 marks Trig Proofs Trigonometric Identity Simplification
Given $\sin \theta + \sin \left( \theta + \frac { \pi } { 3 } \right) = 1$, then $\sin \left( \theta + \frac { \pi } { 6 } \right) =$
A. $\frac { 1 } { 2 }$
B. $\frac { \sqrt { 3 } } { 3 }$
C. $\frac { 2 } { 3 }$
D. $\frac { \sqrt { 2 } } { 2 }$
Given $\sin \theta + \sin \left( \theta + \frac { \pi } { 3 } \right) = 1$, then $\sin \left( \theta + \frac { \pi } { 6 } \right) =$\\
A. $\frac { 1 } { 2 }$\\
B. $\frac { \sqrt { 3 } } { 3 }$\\
C. $\frac { 2 } { 3 }$\\
D. $\frac { \sqrt { 2 } } { 2 }$