Q. Solve the initial value problemy′′+2y′+2y=cosxe−x,y(0)=0,y′(0)=0To check your answer, enter y(π/4) with 3 decimal places
Formulate Differential Equation: First, we need to solve the differential equation y′′+2y′+2y=cosxe−x with the initial conditions y(0)=0 and y′(0)=0.
Solve Characteristic Equation: The characteristic equation for the homogeneous part y′′+2y′+2y=0 is r2+2r+2=0.
Find Homogeneous Solution: Solving the characteristic equation, we get complex roots r=−1±i.
Determine Particular Solution: The general solution for the homogeneous equation is yh=e−x(Acos(x)+Bsin(x)), where A and B are constants.
Apply Initial Conditions: Now, we need to find a particular solution yp for the non-homogeneous equation. We can use the method of undetermined coefficients.
Calculate Complete Solution: Guess yp=e−x(u(x)cos(x)+v(x)sin(x)), where u(x) and v(x) are functions to be determined.
Evaluate Final Result: After differentiating yp and substituting into the non-homogeneous equation, we can solve for u(x) and v(x). However, this step is complex and requires careful calculation.
Evaluate Final Result: After differentiating yp and substituting into the non-homogeneous equation, we can solve for u(x) and v(x). However, this step is complex and requires careful calculation.Once u(x) and v(x) are found, we can write the particular solution yp and combine it with the homogeneous solution yh to get the general solution y=yh+yp.
Evaluate Final Result: After differentiating yp and substituting into the non-homogeneous equation, we can solve for u(x) and v(x). However, this step is complex and requires careful calculation.Once u(x) and v(x) are found, we can write the particular solution yp and combine it with the homogeneous solution yh to get the general solution y=yh+yp.We then apply the initial conditions y(0)=0 and y′(0)=0 to find the constants u(x)0 and u(x)1.
Evaluate Final Result: After differentiating yp and substituting into the non-homogeneous equation, we can solve for u(x) and v(x). However, this step is complex and requires careful calculation.Once u(x) and v(x) are found, we can write the particular solution yp and combine it with the homogeneous solution yh to get the general solution y=yh+yp.We then apply the initial conditions y(0)=0 and y′(0)=0 to find the constants u(x)0 and u(x)1.After finding u(x)0 and u(x)1, we have the complete solution u(x)4. We can then evaluate u(x)5 and round to three decimal places.
Evaluate Final Result: After differentiating yp and substituting into the non-homogeneous equation, we can solve for u(x) and v(x). However, this step is complex and requires careful calculation.Once u(x) and v(x) are found, we can write the particular solution yp and combine it with the homogeneous solution yh to get the general solution y=yh+yp.We then apply the initial conditions y(0)=0 and y′(0)=0 to find the constants u(x)0 and u(x)1.After finding u(x)0 and u(x)1, we have the complete solution u(x)4. We can then evaluate u(x)5 and round to three decimal places.However, I realized I skipped the actual calculations for finding u(x) and v(x), which are essential for solving the problem. This is a mistake, and I need to correct it.
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