If sin 2theta + sin 2phi = 1/2 and cos 2theta | vedclass

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(B) Given equations are:$\sin 2	heta + \sin 2\phi = 1/2$  $(i)$$\cos 2	heta + \cos 2\phi = 3/2$  $(ii)$Squaring and adding equations $(i)$ and $(ii)

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$5/8$

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(B) Given equations are:$\sin 2	heta + \sin 2\phi = 1/2$  $(i)$$\cos 2	heta + \cos 2\phi = 3/2$  $(ii)$Squaring and adding equations $(i)$ and $(ii)$:$(\sin 2	heta + \sin 2\phi)^2 + (\cos 2	heta + \cos 2\phi)^2 = (1/2)^2 + (3/2)^2$$(\sin^2 2	heta + \cos^2 2	heta) + (\sin^2 2\phi + \cos^2 2\phi) + 2(\sin 2	heta \sin 2\phi + \cos 2	heta \cos 2\phi) = 1/4 + 9/4$$1 + 1 + 2\cos(2	heta - 2\phi) = 10/4$$2 + 2\cos(2(	heta - \phi)) = 5/2$$2\cos(2(	heta - \phi)) = 5/2 - 2 = 1/2$$\cos(2(	heta - \phi)) = 1/4$Using the identity $\cos 2A = 2\cos^2 A - 1$:$2\cos^2(	heta - \phi) - 1 = 1/4$$2\cos^2(	heta - \phi) = 1 + 1/4 = 5/4$$\cos^2(	heta - \phi) = 5/8$

If $\sin 2\theta + \sin 2\phi = 1/2$ and $\cos 2\theta + \cos 2\phi = 3/2$,then $\cos^2(\theta - \phi) = $

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