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It appears you have a page from a textbook with trigonometry problems. Since it's in a language I can't identify, I can't give precise solutions, but I can guide you in understanding the trigonometric functions and concepts that may be involved. Here's a general overview of the trigonometric functions: 1. **Sine (sin)**: It represents the ratio of the length of the side opposite the angle to the hypotenuse of a right triangle. 2. **Cosine (cos)**: It represents the ratio of the length of the adjacent side to the hypotenuse. 3. **Tangent (tan)**: It is the ratio of the sine to the cosine, or the opposite side to the adjacent side. 4. **Cotangent (cot), Secant (sec), and Cosecant (csc)**: These are the reciprocals of tangent, cosine, and sine, respectively. For problem-solving in trigonometry: - Use identities like Pythagorean identity: \( \sin^2 \theta + \cos^2 \theta = 1 \). - Angle sum and difference identities can be helpful: - \( \sin(a \pm b) = \sin a \cos b \pm \cos a \sin b \) - \( \cos(a \pm b) = \cos a \cos b \mp \sin a \sin b \) - Understand the unit circle and how angles correspond to points on the circle, which helps visualize sine and cosine values. If you have specific questions or need a particular problem translated or solved, providing context or the specific text might be helpful.