Evaluate the determinants:

\(\begin{bmatrix}cos 15° &-sin 15° \\[0.3em] sin75° & cos75° \\[0.3em] \end{bmatrix}\)

Asked by Aaryan | 1 year ago |  163

1 Answer

Solution :-

|A| = cos15° × cos75° + sin15° x sin75°

We know that cos (A – B) = cos A cos B + Sin A sin B

By substituting this we get, |A| = cos (75 – 15)°

|A| = cos60°

|A| = 0.5

Answered by Sakshi | 1 year ago

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