An Extension of the Legendre-Galerkin Method for Solving Sixth-Order Differential Equations with Variable Polynomial Coefficients

Table 1

Maximum pointwise error of 𝑢−𝑢_𝑁 for 𝑁=20,30,40.

N	𝛾0	𝛾1	𝛾2	LGM	𝛾0	𝛾1	𝛾2	LGM
20	30	1	1	8.66⋅10^−4	1	3	5	9.22⋅10^−4
30				1.67⋅10^−9				1.67⋅10^−9
40				6.10⋅10^−16				6.10⋅10^−16