jika 90°<a<180°dan sin a=4/5,maka cos a adalah

A; Scientific theories are made as explanations to the world around us. They do not have to be written in simple terms, they do not have to be equations (Theory of evolution) and they do not have to be accepted by all the scientists, as it would be impracticable. A successful theory is one that has been used to accurately foretell a future event.

Answered by Anonymous | 2024-06-10

A. Can be used to make accurate predictions. ;

Answered by KnvJ | 2024-06-13

A successful scientific theory is defined by its ability to make accurate predictions about future events. It must also be testable, provide explanatory power, and withstand scrutiny from the scientific community. Therefore, the correct answer is A: Can be used to make accurate predictions.
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Answered by Anonymous | 2024-10-09

Jawaban:Karena 90° < a < 180°, sudut a berada di kuadran II. Di kuadran II, nilai sinus positif dan nilai kosinus negatif. Kita tahu bahwa sin²a + cos²a = 1. Maka, cos²a = 1 - sin²a = 1 - (4/5)² = 1 - 16/25 = 9/25 Oleh karena itu, cos a = ±√(9/25) = ±3/5 Karena a berada di kuadran II, cos a bernilai negatif. Jadi, cos a = -3/5

Answered by claudina2 | 2025-07-11