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Differential Equations

Question
CBSEENMA12033156

Solve the differential equation:
dy over dx minus 2 straight y space equals space 3 straight x.

Solution
The given differential equation is
                 dy over dx minus 2 straight y space equals space 3 straight x
Comparing it with   dy over dx plus space straight P space straight y space equals space straight Q comma space space we space get comma
                      P =  -2,   Q = 3x
    integral straight P space dx space equals space minus 2 space integral space dx space equals space minus 2 straight x
space space space straight I. straight F. space equals space straight e to the power of integral Pdx end exponent space equals space straight e to the power of negative 2 straight x end exponent
Solution of given differential equation is
                   straight y space straight e to the power of integral straight P space dx end exponent space equals space integral straight Q space straight e to the power of integral straight P space dx end exponent dx space plus space straight c
or        straight y space straight e to the power of negative 2 straight x end exponent space equals space integral space 3 space straight x space straight e to the power of negative 2 straight x end exponent space dx plus straight c
or        ye to the power of negative 2 straight x end exponent space equals space 3 space integral space xe to the power of negative 2 straight x end exponent dx plus straight c
or       ye to the power of negative 2 straight x end exponent space equals space 3 space open square brackets straight x fraction numerator straight e to the power of negative 2 straight x end exponent over denominator negative 2 end fraction minus integral 1. space fraction numerator straight e to the power of negative 2 straight x end exponent over denominator negative 2 end fraction dx close square brackets plus straight c      
or         ye to the power of negative 2 straight x end exponent space equals negative 3 over 2 xe to the power of negative 2 straight x end exponent plus 3 over 2 integral straight e to the power of negative 2 end exponent dx plus straight c
or        ye to the power of negative 2 straight x end exponent space equals space minus 3 over 2 xe to the power of negative 2 straight x end exponent plus 3 over 2 fraction numerator straight e to the power of negative 2 straight x end exponent over denominator negative 2 end fraction plus straight c
or                             straight y equals negative 3 over 2 straight x minus 3 over 4 plus ce to the power of 2 straight x end exponent
which is required solution. 

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