CEE Kerala Engineering CEE Kerala Engineering Solved Paper-2004

  • question_answer
    The solution of\[\frac{dy}{dx}+y\tan x=\sec x\]is:

    A)  \[y\text{ }sec\text{ }x=tan\text{ }x+c\]

    B)  \[y\text{ }tan\text{ }x=sec\text{ }x+c\]

    C)  \[tan\text{ }x=y\text{ }tan\text{ }x+c\]

    D)  \[x\text{ }sec\text{ }x=tan\text{ }y+c\]

    E)  \[x\text{ }tan\text{ }x=y\text{ }tan\text{ }x+c\]

    Correct Answer: A

    Solution :

    Given equation is \[\frac{dy}{dx}+y\tan x=\sec x\] Here,\[P=tan\text{ }x\]and\[Q=sec\text{ }x\] \[\therefore \]  \[IF={{e}^{\int{P\,dx}}}={{e}^{\int{\tan x\,dx}}}\]                                 \[={{e}^{\log x\sec x}}=\sec x\] \[\therefore \]Solution is                 \[y.\sec x=\int{{{\sec }^{2}}x}\,dx+c\] \[\Rightarrow \]               \[y.\sec x=\tan x+c\]


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