Find the values of trigonometric ratios \( cos \dfrac{-25π}{4}\)

Asked by Sakshi | 1 year ago |  256

1 Answer

Solution :-

cos (-1125)°

= cos (1125)°

Since, 1125o lies in the I quadrant in which cosine function is positive.

cos (1125)° = cos (90×12 + 45)°

= cos 45°

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

Answered by Sakshi | 1 year ago

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