Step-by-step derivation
S001 · implies
Before
source roles = [qf-mod50-trap-composite-value, trap-composite-value]
After
derived = [[nodes, endpoint_values, individual_trapezoid_terms, trapezoid_value, width_convention]]
Conditions: none
List this scalar/label/set/point answer role or mode-specific ordered fields,not an imposed universal tuple.Retain legacy domain/underscore operation and integer fractions with/1;original bilingual snapshots stay unchanged.
Step identifiers and dependencies
Rule: source_answer_roles_or_ordered_fields_without_JS · Uses: G001
S002 · calculation
Before
Trapezoid ORIGINAL ORIGINAL width0 := sub(1, 0)
After
Trapezoid ORIGINAL ORIGINAL width0 = 1
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S001
S003 · calculation
Before
Trapezoid ORIGINAL ORIGINAL width1 := sub(10, 1)
After
Trapezoid ORIGINAL ORIGINAL width1 = 9
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S002
S004 · calculation
Before
Trapezoid ORIGINAL ORIGINAL width over2 interval0 := div(1, 2)
After
Trapezoid ORIGINAL ORIGINAL width over2 interval0 = 1/2
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S003
S005 · calculation
Before
Trapezoid ORIGINAL ORIGINAL endpoint sum interval0 := sum(7, 8)
After
Trapezoid ORIGINAL ORIGINAL endpoint sum interval0 = 15
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S004
S006 · calculation
Before
Trapezoid ORIGINAL ORIGINAL individual trapezoid interval0 := mul(1/2, 15)
After
Trapezoid ORIGINAL ORIGINAL individual trapezoid interval0 = 15/2
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S005
S007 · implies
Before
source roles = [Trapezoid ORIGINAL, 0, 0, 1, 7, 8]
After
derived = [1, 1/2, 15, 15/2]
Conditions: none
Use the own width and aligned endpoints of this ORIGINAL interval times the endpoint average.Widths may differ and values may be negative;do not sort or replace all widths with the first.
Step identifiers and dependencies
Rule: Trapezoid_EACH_original_interval_own_width_and_aligned_endpoints · Uses: G001, S006
S008 · calculation
Before
Trapezoid ORIGINAL ORIGINAL width over2 interval1 := div(9, 2)
After
Trapezoid ORIGINAL ORIGINAL width over2 interval1 = 9/2
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S007
S009 · calculation
Before
Trapezoid ORIGINAL ORIGINAL endpoint sum interval1 := sum(8, 10)
After
Trapezoid ORIGINAL ORIGINAL endpoint sum interval1 = 18
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S008
S010 · calculation
Before
Trapezoid ORIGINAL ORIGINAL individual trapezoid interval1 := mul(9/2, 18)
After
Trapezoid ORIGINAL ORIGINAL individual trapezoid interval1 = 81
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S009
S011 · implies
Before
source roles = [Trapezoid ORIGINAL, 1, 1, 10, 8, 10]
After
derived = [9, 9/2, 18, 81]
Conditions: none
Use the own width and aligned endpoints of this ORIGINAL interval times the endpoint average.Widths may differ and values may be negative;do not sort or replace all widths with the first.
Step identifiers and dependencies
Rule: Trapezoid_EACH_original_interval_own_width_and_aligned_endpoints · Uses: G001, S010
S012 · calculation
Before
Trapezoid ORIGINAL ORIGINAL trapezoid running total0 := sum(0, 15/2)
After
Trapezoid ORIGINAL ORIGINAL trapezoid running total0 = 15/2
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S011
S013 · calculation
Before
Trapezoid ORIGINAL ORIGINAL trapezoid running total1 := sum(15/2, 81)
After
Trapezoid ORIGINAL ORIGINAL trapezoid running total1 = 177/2
Conditions: none
Substitute original roles exactly,without floating approximation or changed operands;extra teaching identities add no source-domain restrictions.
Step identifiers and dependencies
Rule: exact_rational_arithmetic · Uses: G001, S012
S014 · implies
Before
source roles = [Trapezoid ORIGINAL, [0, 1, 10], [7, 8, 10]]
After
derived = [[0, 1, 10], [7, 8, 10], [1, 9], [15/2, 81], 177/2]
Conditions: none
A complete partition is STRICTLY increasing in original order,with n+1 aligned nodes/values for n intervals;the24-node cap is not the vector8 cap.The table determines this sum,not a unique integral without a full integrand.
Step identifiers and dependencies
Rule: Trapezoid_COMPLETE_partition_n_intervals_nplus1_nodes_no_unique_integrand · Uses: G001, S013