मराठी

If Tan a = 5 6 and Tan B = 1 11 , Prove that a + B = π 4 .

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प्रश्न

 If \[\tan A = \frac{5}{6}\text{ and }\tan B = \frac{1}{11}\], prove that \[A + B = \frac{\pi}{4}\].

थोडक्यात उत्तर
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उत्तर

We have: 
\[\tan A = \frac{5}{6}\text{ and }\tan B = \frac{1}{11}\]
\[\text{ Therefore, }\tan\left( A + B \right) = \frac{\tan A + \tan B}{1 - \tan A \tan B}\]
\[ \Rightarrow \tan\left( A + B \right) = \frac{\tan A + \tan B}{1 - \tan A \tan B}\]
\[ \Rightarrow \tan\left( A + B \right) = \frac{\frac{5}{6} + \frac{1}{11}}{1 - \frac{5}{6} \times \frac{1}{11}}\]
\[ \Rightarrow \tan\left( A + B \right) = \frac{\frac{61}{66}}{\frac{61}{66}}\]
\[ \Rightarrow \tan\left( A + B \right) = 1\]
\[ \Rightarrow \tan\left( A + B \right) = \tan\left( \frac{\pi}{4} \right)\]
\[\text{ Therefore, }A + B = \frac{\pi}{4} . \]
Hence proved .

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पाठ 7: Values of Trigonometric function at sum or difference of angles - Exercise 7.1 [पृष्ठ २०]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 7 Values of Trigonometric function at sum or difference of angles
Exercise 7.1 | Q 14.1 | पृष्ठ २०

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