CET Karnataka Engineering CET - Karnataka Engineering Solved Paper-2010

  • question_answer
    \[(\sin \theta +\cos \theta )\,(\tan \theta +cot\theta )\] is equal to

    A) \[\sin \theta \,\cos \theta \]

    B) \[1\]

    C) \[\sec \theta +\text{cosec}\theta \]

    D) \[\sec \theta \,\,\text{cosec}\theta \]

    Correct Answer: A , C

    Solution :

    Solution :

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


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