The function is .
The general form of sine function is .
Where is amplitude and period
.
Compare the function with general form of sine function.
\Here amplitude is .
The period is .
Therefore, the sine wave starts from , completes one cycle at
and completes two cycles at
.
The negative sign indicates that the function flips about -axis.
Observe the graphs:
\The graph (D) matches to the characteristics of the function .
Hence, the graph (D) is the correct choice.
\The graph (D) is the correct choice.