If cos is 1/3 what is sin?

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Understanding the Relationship Between Sine and Cosine in Trigonometry

In trigonometry, the sine (sin) and cosine (cos) functions are closely related. When the cosine of an angle is given as 1/3, we can use the Pythagorean identity sin^2(x) + cos^2(x) = 1 to find the sine value. First, we square 1/3 to get 1/9. Then, subtracting this from 1 gives us sin^2(x) = 8/9. Taking the square root of 8/9 gives sin(x) = √(8/9) = 2√2/3 or approximately 0.9428.

Understanding the relationship between sine and cosine is essential in trigonometry. These functions are used to describe the relationships between the sides and angles of a right triangle. The sine function represents the ratio of the length of the side opposite an angle to the hypotenuse, while cosine represents the ratio of the adjacent side to the hypotenuse. By understanding how these functions are connected, we can solve various mathematical problems involving angles and sides in triangles. Practice and familiarity with these functions are key to mastering trigonometry.