28 Test file number 48

  28.1 Problem number 9

Test folder name:

test_cases/1_Algebraic_functions/1.2_Trinomial_products/1.2.3_General/48_1.2.3.4-f_x-^m-d+e_x^n-^q-a+b_x^n+c_x^-2_n-^p