(a) Comparison of absolute errors of 1st order OHAM solution and 1st order VIM solution for Example 4 at and various values of t. (b) Comparison of absolute errors of 1st order OHAM solution and 1st order VIM solution for Example 4 at and various values of t. (c) Comparison of absolute errors of 1st order OHAM solution and 1st order VIM solution for Example 4 at and various values of t. (d) Comparison of absolute errors of 1st order OHAM solution and 1st order VIM solution for Example 4 at and various values of t.