document.write( "Question 1183480: consider the differential equation 2y'' -13y' -7y = 0\r
\n" ); document.write( "\n" ); document.write( "a. Show that, for any constants A and B, the following is a solution to the above differential equation: \"+y+=+Ae%5E%28-9x%29%2BBe%5E%28x%2F3%29+\"\r
\n" ); document.write( "\n" ); document.write( "b. Find the values A and B that make the above general solution into a solution for the following initial value problem: 2y'' - 13y' - 7y = 0 ; y(0) = 3, y'(0) = -5
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Algebra.Com's Answer #813835 by robertb(5830)\"\" \"About 
You can put this solution on YOUR website!
Your differential equation is 2y'' -13y' -7y = 0, which is a homogeneous linear 2nd order ODE with constant coefficients. As such, its characteristic equation is \r
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\n" ); document.write( "\n" ); document.write( "\"2%2Alambda%5E2+-+13%2Alambda+-+7+=+%282%2Alambda+%2B+1%29%28lambda+-+7%29+=+0\"\r
\n" ); document.write( "\n" ); document.write( "==> \"lambda+=+-1%2F2\", \"lambda+=+7\".\r
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\n" ); document.write( "\n" ); document.write( "As such, the general solution ought to be \"y+=+A%2Ae%5E%28-x%2F2%29+%2B+B%2Ae%5E%287x%29\" for any arbitrary constants A and B, and NOT \"+y+=+Ae%5E%28-9x%29%2BBe%5E%28x%2F3%29+\" as you mentioned.\r
\n" ); document.write( "\n" ); document.write( "I have done the necessary correction to your problem. I guess you will be able to do it now.
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