Let ` cos (alpha+beta) = 4/5` and `sin(alpha-beta)=5/13 ` where `0 – InterviewSolution

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1.	Let ` cos (alpha+beta) = 4/5` and `sin(alpha-beta)=5/13 ` where `0
Answer» Correct Answer - D We have, `cos(alpha+beta)=4/5and sin(alpha-beta)=5/13`n `impliestan(alpha+beta)=3/5and tan(alpha-beta)=15/12` `thereforetan 2alpha=tan(alpha+beta+alpha-beta)=(tan(alpha+beta)+an(alpha-beta))/(1-tan(alpha+beta)tan(alpha-beta))` `impliestan 2alpha=((3)/(5)+(5)/(12))/(1-(3)/(5)xx(5)/(12))=56/33`

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