Sin^3 (2x).cos6x+sin6x.cos^3 ( 2x)= 3/8

Sin^3 (2x).cos6x+sin6x.cos^3 ( 2x)= 3/8
<=>cos6x.(3sin2x-sin6x)/4 +sin6x.(3cos2x-cos6x)/4 = 3/8
<=>sin2x.cos6x+cos2x.sin6x = 1/2
<=>sin(2x+6x) = 1/2
<=>sin8x =1/2

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