c ) sin alpha * (2cos 4alpha + 2cos 2alpha + 1) = - Dicamon

Question

c ) sin alpha * (2cos 4alpha + 2cos 2alpha + 1) = sin 5alpha ; d ) (cos(alpha - beta))/(cos(alpha + beta)) = (1 + tan alpha * tan beta)/(1 - tan alpha * tan bet

Answer

(2cos 4alpha + 2cos 2alpha + l) = sin 5alpha; sqrt(T) = sin alpha * (2cos 4a + 2cos 2alpha + 1); =2.cos 4x.sin alpha+2 cos 2 alpha.sin alpha+sin alpha; =sin 5 alpha-sin 3a+sin 3

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