Page 60 - Schaum's Outline of Differential Equations
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CHAP. 6]               LINEAR FIRST-ORDER  DIFFERENTIAL  EQUATIONS                     43



                                           Solved Problems


         6.1.  Find  an integrating factor for y'  — 3y = 6.
                  The differential  equation  has the form of Eq. (6.1), withp(x)  = -3  and q(x) = 6, and is linear.  Here



               so (6.2) becomes




         6.2.  Solve the differential  equation in the previous problem.
                  Multiplying the  differential  equation  by the integrating factor defined by (1) of Problem  6.1, we obtain





               Integrating both  sides of this last equation with respect  to x, we  have









         6.3.  Find an integrating factor for y' -  2xy = x.
                  The differential  equation  has the form of Eq. (6.1), with p(x)  = -2x  and q(x) = x, and is linear.  Here


               so (6.2) becomes





         6.4.  Solve the differential  equation in the previous problem.
                  Multiplying the  differential  equation  by the integrating factor defined by (1) of Problem 6.3, we obtain




               Integrating both  sides of this last equation with respect  to x, we find  that













                                                  4
         6.5.  Find an integrating factor for y' + (4lx)y  = x .
                                                                           4
                  The  differential  equation  has the form of Eq.  (6.1), with p(x)  = 4/x  and q(x) = x , and  is linear.  Here
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