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x(t)=ft Solve the given initial-value problem: d²/dt² +9x = 5sin(3t), x(0) = 6, x'(0) = -1 You can proceed with solving this initial-value problem.

User MatheM
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1 Answer

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Final answer:


\(x(t) = (1)/(18)(2\sin(3t) - 3\cos(3t)) + (31)/(18)e^(-3t) + (19)/(6)\)the initial conditions
\(x(0) = 6\) and \(x'(0) = -1\),we solve for the constants
\(A\) and \(B\) in the complementary function. Substituting the values yields
\(A = (31)/(18)\) and \(B = (19)/(6)\).

Step-by-step explanation:

The solution to the initial-value problem
\(x(t) = ft\) with \(d^2/dt^2 + 9x = 5\sin(3t)\), \(x(0) = 6\), and \(x'(0) = -1\)involves several steps. First, we identify the complementary function by solving the associated homogeneous equation
\(d^2/dt^2 + 9x = 0\),resulting in
\(x_c(t) = A\cos(3t) + B\sin(3t)\).Then, we determine the particular integral of the non-homogeneous term,
\(5\sin(3t)\), which takes the form
\(x_p(t) = (1)/(18)(2\sin(3t) - 3\cos(3t))\).Next, we combine the complementary function and particular integral to find the general solution
\(x(t) = x_c(t) + x_p(t)\).

Using the initial conditions
\(x(0) = 6\) and \(x'(0) = -1\),we solve for the constants
\(A\) and \(B\) in the complementary function. Substituting the values yields
\(A = (31)/(18)\) and \(B = (19)/(6)\). Therefore, the complete solution for
\(x(t)\) is \(x(t) = (1)/(18)(2\sin(3t) - 3\cos(3t)) + (31)/(18)e^(-3t) + (19)/(6)\).

This solution satisfies the initial-value problem by incorporating the general solution with the determined constants, providing the function
\(x(t)\) that satisfies the given differential equation along with the specified initial conditions.

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User Nagarjun Prasad
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