2. Solved Papers
  3. BCECE Engineering

BCECE Engineering BCECE Engineering Solved Paper-2009

  • question_answer
    A particular solution of \[\log \left( \frac{dy}{dx} \right)=3x+4y,y(0)=0\]is

    A) \[{{e}^{3x}}+3{{e}^{-4y}}=4\]    

    B)  \[4{{e}^{3x}}-3{{e}^{-4y}}=3\]

    C)  \[3{{e}^{3x}}+4{{e}^{-4y}}=7\]

    D)  \[4{{e}^{3x}}+3{{e}^{-4y}}=7\]

    Correct Answer: C

    Solution :

    Give, \[\log \left( \frac{dy}{dx} \right)=3x+4y\] \[\Rightarrow \]\[\frac{dy}{dx}={{e}^{3x}}{{e}^{4y}}\] \[\Rightarrow \]\[{{e}^{-4y}}dy={{e}^{3x}}dx\] On integrating both sides, we get \[-4{{e}^{-4y}}=3{{e}^{3x}}+c\]                 At           \[x=0,y=0,\]                                 \[-4=3+c\Rightarrow c=-7\] \[\therefore \] Solution is \[4{{e}^{-4y}}+3{{e}^{3x}}=7\]


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