Question

( =1 quad 4 cos frac{7 theta}{2} sin theta cdot sin left(-frac{theta}{2}right) )
( Rightarrow-4 cos frac{7 theta}{2} cdot sin theta cdot sin frac{theta}{2} )
( therefore lambda=-4 quad ) (3) ( quad ) Plz give
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# 1) 10 + 573 (b) none of these If cos20 - cos30 - cos40 + cos50 = a sinsino coso, then 2 is equals to (A) - 2 (B) = 4

Solution