Target Exam

CUET

Subject

-- Applied Mathematics - Section B2

Chapter

Algebra

Question:

The value of the determinant

$Δ = \begin{vmatrix}sin 2\alpha  & sin ( \alpha + \beta) & sin (\alpha + \gamma )\\sin (\beta + \gamma ) & sin 2 \beta  & sin (\gamma + \beta)\\(sin \gamma + \alpha ) & sin ( \gamma + \beta ) & sin 2 \gamma \end{vmatrix},$  is

Options:

0

$sin^2\alpha + sin^2 \beta + sin^2 \gamma $

$\frac{3}{2}$

none of these

Correct Answer:

0

Explanation:

The correct answer is option (1) : 0

We have,

$Δ=\begin{vmatrix}sin \alpha & cos \alpha  &0 \\sin \beta  & cos\beta  & 0\\sin \gamma & cos \gamma  & 0\end{vmatrix}\begin{vmatrix}cos\alpha & sin\alpha  &0 \\cos\beta  & sin\beta  & 0\\cos\gamma & sin\gamma  & 0\end{vmatrix}$

$⇒Δ=0×0=0$