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CBSE Class 10 Answered

Trigonometry
Asked by | 08 Oct, 2009, 11:45: PM
answered-by-expert Expert Answer

cos A = (1-sin2A) = (1-1/10) = 3/10.

cos B = 2/5

 sin (A+B) = sin A cos B + cos A sin B

        = (1/10)(2/5) + (3/10)(1/5)

        = (1/50)(2+3)

i.e. 5/50 = 1/2.

sin (A+B) =  1/2

sin 45 = 1/2,  A + B = 45,

Regards,

Team,

TopperLearning.

 

Answered by | 09 Oct, 2009, 10:59: AM

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