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Find the value of the remainig(all) func...

Find the value of the remainig(all) function in each of the following :
(i) `"sin"theta theta =(3)/(5), theta` in quadrient II
(ii) `costheta=-(3)/(5),theta` in quadrient III
(iii) `"tan" theta =(4)/(3), theta` in quadrant III
(iv) `cot theta=-(5)/(12),theta` in quadrant IV
(vi) `"sin" theta sectheta =- 1, theta` in quadant II.

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To solve the given trigonometric problems step by step, we will use the fundamental relationships between the trigonometric functions and the properties of triangles. ### (i) Given: \( \sin \theta = \frac{3}{5} \), \( \theta \) in Quadrant II 1. **Find \( \cos \theta \)**: - Use the Pythagorean identity: \( \sin^2 \theta + \cos^2 \theta = 1 \) - Substitute \( \sin \theta \): \[ \left(\frac{3}{5}\right)^2 + \cos^2 \theta = 1 \] \[ \frac{9}{25} + \cos^2 \theta = 1 \] \[ \cos^2 \theta = 1 - \frac{9}{25} = \frac{16}{25} \] \[ \cos \theta = -\frac{4}{5} \quad (\text{negative in Quadrant II}) \] 2. **Find \( \tan \theta \)**: - \( \tan \theta = \frac{\sin \theta}{\cos \theta} \) \[ \tan \theta = \frac{\frac{3}{5}}{-\frac{4}{5}} = -\frac{3}{4} \] 3. **Find \( \cot \theta \)**: - \( \cot \theta = \frac{1}{\tan \theta} = -\frac{4}{3} \) 4. **Find \( \sec \theta \)**: - \( \sec \theta = \frac{1}{\cos \theta} = -\frac{5}{4} \) 5. **Find \( \csc \theta \)**: - \( \csc \theta = \frac{1}{\sin \theta} = \frac{5}{3} \) ### Summary for (i): - \( \cos \theta = -\frac{4}{5} \) - \( \tan \theta = -\frac{3}{4} \) - \( \cot \theta = -\frac{4}{3} \) - \( \sec \theta = -\frac{5}{4} \) - \( \csc \theta = \frac{5}{3} \) --- ### (ii) Given: \( \cos \theta = -\frac{3}{5} \), \( \theta \) in Quadrant III 1. **Find \( \sin \theta \)**: - Use the Pythagorean identity: \[ \sin^2 \theta + \left(-\frac{3}{5}\right)^2 = 1 \] \[ \sin^2 \theta + \frac{9}{25} = 1 \] \[ \sin^2 \theta = 1 - \frac{9}{25} = \frac{16}{25} \] \[ \sin \theta = -\frac{4}{5} \quad (\text{negative in Quadrant III}) \] 2. **Find \( \tan \theta \)**: - \( \tan \theta = \frac{\sin \theta}{\cos \theta} \) \[ \tan \theta = \frac{-\frac{4}{5}}{-\frac{3}{5}} = \frac{4}{3} \] 3. **Find \( \cot \theta \)**: - \( \cot \theta = \frac{1}{\tan \theta} = \frac{3}{4} \) 4. **Find \( \sec \theta \)**: - \( \sec \theta = \frac{1}{\cos \theta} = -\frac{5}{3} \) 5. **Find \( \csc \theta \)**: - \( \csc \theta = \frac{1}{\sin \theta} = -\frac{5}{4} \) ### Summary for (ii): - \( \sin \theta = -\frac{4}{5} \) - \( \tan \theta = \frac{4}{3} \) - \( \cot \theta = \frac{3}{4} \) - \( \sec \theta = -\frac{5}{3} \) - \( \csc \theta = -\frac{5}{4} \) --- ### (iii) Given: \( \tan \theta = \frac{4}{3} \), \( \theta \) in Quadrant III 1. **Find \( \sin \theta \)**: - Use \( \tan \theta = \frac{\sin \theta}{\cos \theta} \) and the identity \( \sin^2 \theta + \cos^2 \theta = 1 \). - Let \( \sin \theta = 4k \) and \( \cos \theta = -3k \) (since \( \tan \theta = \frac{4}{3} \)). \[ (4k)^2 + (-3k)^2 = 1 \] \[ 16k^2 + 9k^2 = 1 \] \[ 25k^2 = 1 \quad \Rightarrow \quad k^2 = \frac{1}{25} \quad \Rightarrow \quad k = \frac{1}{5} \] \[ \sin \theta = 4k = \frac{4}{5}, \quad \cos \theta = -3k = -\frac{3}{5} \] 2. **Find \( \cot \theta \)**: - \( \cot \theta = \frac{1}{\tan \theta} = \frac{3}{4} \) 3. **Find \( \sec \theta \)**: - \( \sec \theta = \frac{1}{\cos \theta} = -\frac{5}{3} \) 4. **Find \( \csc \theta \)**: - \( \csc \theta = \frac{1}{\sin \theta} = \frac{5}{4} \) ### Summary for (iii): - \( \sin \theta = -\frac{4}{5} \) - \( \tan \theta = \frac{4}{3} \) - \( \cot \theta = \frac{3}{4} \) - \( \sec \theta = -\frac{5}{3} \) - \( \csc \theta = -\frac{5}{4} \) --- ### (iv) Given: \( \cot \theta = -\frac{5}{12} \), \( \theta \) in Quadrant IV 1. **Find \( \tan \theta \)**: - \( \tan \theta = -\frac{12}{5} \) 2. **Find \( \sin \theta \)**: - Let \( \sin \theta = -12k \) and \( \cos \theta = 5k \) (since \( \cot \theta = \frac{1}{\tan \theta} \)). \[ (-12k)^2 + (5k)^2 = 1 \] \[ 144k^2 + 25k^2 = 1 \] \[ 169k^2 = 1 \quad \Rightarrow \quad k^2 = \frac{1}{169} \quad \Rightarrow \quad k = \frac{1}{13} \] \[ \sin \theta = -\frac{12}{13}, \quad \cos \theta = \frac{5}{13} \] 3. **Find \( \sec \theta \)**: - \( \sec \theta = \frac{1}{\cos \theta} = \frac{13}{5} \) 4. **Find \( \csc \theta \)**: - \( \csc \theta = \frac{1}{\sin \theta} = -\frac{13}{12} \) ### Summary for (iv): - \( \sin \theta = -\frac{12}{13} \) - \( \tan \theta = -\frac{12}{5} \) - \( \cot \theta = -\frac{5}{12} \) - \( \sec \theta = \frac{13}{5} \) - \( \csc \theta = -\frac{13}{12} \) --- ### (v) Given: \( \sin \theta \sec \theta = -1 \), \( \theta \) in Quadrant II 1. **Use the identity**: - \( \sec \theta = \frac{1}{\cos \theta} \) - Thus, \( \sin \theta \cdot \frac{1}{\cos \theta} = -1 \) - Rearranging gives \( \sin \theta = -\cos \theta \) 2. **Find \( \sin \theta \)**: - Since \( \theta \) is in Quadrant II, \( \sin \theta \) is positive and \( \cos \theta \) is negative. - Let \( \sin \theta = k \) and \( \cos \theta = -k \). - Then \( k = -(-k) = k \) leads to \( k = \frac{1}{\sqrt{2}} \). 3. **Find \( \cos \theta \)**: - \( \cos \theta = -\frac{1}{\sqrt{2}} \) 4. **Find \( \tan \theta \)**: - \( \tan \theta = \frac{\sin \theta}{\cos \theta} = \frac{\frac{1}{\sqrt{2}}}{-\frac{1}{\sqrt{2}}} = -1 \) 5. **Find \( \cot \theta \)**: - \( \cot \theta = -1 \) 6. **Find \( \sec \theta \)**: - \( \sec \theta = -\sqrt{2} \) 7. **Find \( \csc \theta \)**: - \( \csc \theta = \sqrt{2} \) ### Summary for (v): - \( \sin \theta = \frac{1}{\sqrt{2}} \) - \( \tan \theta = -1 \) - \( \cot \theta = -1 \) - \( \sec \theta = -\sqrt{2} \) - \( \csc \theta = \sqrt{2} \) ---
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