document.write( "Question 1115049: Please help me answer the following question:\r
\n" ); document.write( "\n" ); document.write( "(a) Determine the particular solution of the equation
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\n" ); document.write( "\"+d%5E2%2Fdx%5E2+-+3%28dy%2Fdx%29+=+9+\"\r
\n" ); document.write( "\n" ); document.write( "given the initial conditions:
\n" ); document.write( "y(0) = 0, y'(0) = 0
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Algebra.Com's Answer #730041 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
this is a second-order linear differential equation which is nonhomogeneous
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\n" ); document.write( "Note the general form is
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\n" ); document.write( "1) a(d^2 y/dx^2) + b(dy/dx) + c(x)y = G(x) where a, b, c, are constants and G is a continuous functions not equal to 0 for some x
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\n" ); document.write( "The complementary form is
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\n" ); document.write( "2) a(d^2 y/dx^2) + b(dy/dx) + c(x)y = G(x) where a, b, c, are constants and G is a continuous functions equal to 0 for some x
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\n" ); document.write( "The general solution is given by the formula
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\n" ); document.write( "y(x) = y(p) (x) + y(c) (x), where y(p) is a particular solution to equation 1 and y(c) is a general solution to equation 2
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\n" ); document.write( "we are given the problem
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\n" ); document.write( "(d^2 y/d x^2) - 3(dy/dx) = 9
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\n" ); document.write( "solve the equation 2 form
\n" ); document.write( "r^2 -3r = 0
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\n" ); document.write( "r(r-3) = 0
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\n" ); document.write( "r=0 and r=3
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\n" ); document.write( "So the solution to equation 2 is
\n" ); document.write( ":
\n" ); document.write( "y(c) = c(1)e^(0 * x) + c(2)e^-3x = c(1) +c(2)e^(-3x)
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\n" ); document.write( "since G(x) = 9 is a linear equation, we are looking for a particular solution of the form
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\n" ); document.write( "y(p) (x) = Bx +C
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\n" ); document.write( "y'(p) = B and y''(p) = 0
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\n" ); document.write( "now substitute into the given equation
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\n" ); document.write( "0 -3B = 9
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\n" ); document.write( "polynomials are equal when their coefficients are equal
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\n" ); document.write( "B = -3
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\n" ); document.write( "the general solution is
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\n" ); document.write( "y(x) = c(1) + c(2)e^(-3x) + 9
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\n" ); document.write( "y(0)=0, then
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\n" ); document.write( "c(1) +c(2) +9 = 0
\n" ); document.write( ":
\n" ); document.write( "y' = -3c(2)e^(-3x)
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\n" ); document.write( "y'(0) = 0
\n" ); document.write( ":
\n" ); document.write( "0 = -3c(2)
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\n" ); document.write( "c(2) = 0 and c(1) = -9
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\n" ); document.write( "the solution to the initial value problem is
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\n" ); document.write( "y(x) = -9 +0 +9 = 0
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