﻿ If x = sin α, y = sin β, z = sin (α + β) then cos (α + β) = : Kaysons Education

# If x = Sin α, y = Sin β, z = Sin (α + β) Then Cos (α + β) =

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## Question

### Solution

Correct option is

z2 – x2 – y2 = sin2 (α + β) – sin2 α – sin2 β

= sin (α + β + α) sin (α + β - α) – sin2 β

= sin β [sin (2α + β) – sin β]

#### SIMILAR QUESTIONS

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The value of

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Is zero if

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is equal to

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or equal to

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Q10