\left. \begin{array} { l } { 2 \operatorname { sin } ^ { 2 } \beta + 4 \operatorname { cos } ( \alpha + \beta ) \operatorname { sin } \alpha \operatorname { sin } \beta + \operatorname { cos } 2 ( \alpha + \beta ) = } \\ { ( a ) \operatorname { sin } 2 \alpha } \\ { ( c ) \operatorname { cos } 2 \alpha } & { ( d ) \operatorname { sin } 2 \beta } \end{array} \right.

\left. \begin{array} { l } { 2 \operatorname { sin } ^ { 2 } \beta + 4

1.	\left. \begin{array} { l } { 2 \operatorname { sin } ^ { 2 } \beta + 4 \operatorname { cos } ( \alpha + \beta ) \operatorname { sin } \alpha \operatorname { sin } \beta + \operatorname { cos } 2 ( \alpha + \beta ) = } \\ { ( a ) \operatorname { sin } 2 \alpha } \\ { ( c ) \operatorname { cos } 2 \alpha } & { ( d ) \operatorname { sin } 2 \beta } \end{array} \right.
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