Find the values of trigonometric ratios \( cos \dfrac{19π}{4}\)

Asked by Sakshi | 1 year ago |  102

1 Answer

Solution :-

= cos 855°

= cos (90×9 + 45)°

Since, 855° lies in the II quadrant in which the cosine function is negative.

cos 855° = cos (90×9 + 45)°

= – sin 45°

\(- \dfrac{1}{\sqrt{2}}\)

Answered by Sakshi | 1 year ago

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