If the determinant `|(cos2x,sin^2 x,cos 4x),(sin^2 x,cos 2x,cos^2 x),(cos 4x,cos^2 x,cos 2x)|` is expanded in powers of `sin x`, then the constant term is
A. 1
B. 0
C. -1
D. 2

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1 Answers

Correct Answer - C
`|{:(1-2 sin^(2)x,,sin^(2)x,,1-8 sin^(2)x(1-sin^(2)x)),(sin^(2)x,,1-sin^(2)x,,1-sin^(2)x),(1-8sin^(2)x(1-sin^(2)x),,1-sin^(2)x,,1-sin^(2)x):}|`
The required constant terms is
`|{:(1,,0,,1),(0,,1,,1),(1,,1,,1):}|+|{:(1,,0,,0),(0,,1,,1),(1,,1,,0):}|=1(10 -1)=-1`

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