10th Class Mathematics Introduction to Trigonometry Question Bank Trigonometry

  • question_answer
    \[(cosec\theta -sin\theta )(sec\theta -\cos \theta )(tan\theta +\cot \theta )\] simplifies to

    A) \[0\]

    B) \[1\]

    C) \[\tan \theta \]

    D) \[cot\theta \]

    Correct Answer: B

    Solution :

     \[(\text{cosec }\theta \text{-sin}\theta \text{)}\,\text{(sec}\theta \text{-cos}\,\theta \text{)}\,\text{(tan}\theta \text{+cot }\theta \text{)}\] \[=\left( \frac{1}{\sin \theta }-\sin \theta  \right)\,\left( \frac{1}{\cos \theta }-\cos \theta  \right)\,\left( \frac{\sin \theta }{\cos \theta }+\frac{\cos \theta }{\sin \theta } \right)\] \[=\frac{1-{{\sin }^{2}}\theta }{\sin \theta }\times \frac{1-{{\cos }^{2}}\theta }{\cos \,\theta }\times \frac{{{\sin }^{2}}\theta +{{\cos }^{2}}\theta }{\sin \theta \,\cos \theta }\] \[=\frac{{{\cos }^{2}}\theta }{{{\sin }^{2}}\theta }\times \frac{{{\sin }^{2}}\theta }{\cos \theta }\times \frac{1}{\sin \theta \,cos\theta }\] \[=1\]


You need to login to perform this action.
You will be redirected in 3 sec spinner