$Error=\left|Exact7-u\right|$

$u=\cos \left(x\right)+1.345517155-\frac{5{\pi }^2}{144}$

$Exact7=1+\cos \left(x\right)$

x

0.0191161

1.0807173

1.0998334

0.1

0.0191161

1.1795532

1.1986693

0.2

0.0191161

1.2764041

1.2955202

0.3

0.0191161

1.3703022

1.3894183

0.4

0.0191161

1.4603094

1.4794255

0.5

0.0191161

1.5455264

1.5646425

0.6

0.0191161

1.6251016

1.6442177

0.7

0.0191161

1.6982400

1.7173561

0.8

0.0191161

1.7642108

1.7833269

0.9

0.0191161

1.8223549

1.8414710

1.0