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R0056-28690 · q-20261005-advance-20261006-r03-rate-of-change-0090
On the full real domain, let q:R→R be q(x)=(15)(x−(2))²+(2), with a≠0. For distinct inputs 1 and 17, find the average rate of change. Give a reduced fraction with positive denominator, retaining /1 for integers.
G001 — On the full real domain, let q:R→R be q(x)=(15)(x−(2))²+(2), with a≠0. For distinct inputs 1 and 17, find the average rate of change. Give a reduced fraction with positive denominator, retaining /1 for integers.Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.
Before
source roles = [qf-rate-quadratic-average, quadratic_average]
After
derived = [exact_quadratic_endpoint_average_not_derivative]
Conditions: none
Use the declared scalar/set/Yes-No/fraction answer role;integer fractions retain/1.Do not add an undeclared domain or change original bilingual data,formulas or questions.
Rule: R56_source_answer_role_and_EXACT_family_interface · Uses: G001
Before
Rate ORIGINAL x1 minus x0 := sub(17, 1)
After
Rate ORIGINAL x1 minus x0 = 16
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S001
Before
Rate quadratic ORIGINAL displacement0 := sub(1, 2)
After
Rate quadratic ORIGINAL displacement0 = -1
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S002
Before
Rate quadratic ORIGINAL square0 := mul(-1, -1)
After
Rate quadratic ORIGINAL square0 = 1
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S003
Before
Rate quadratic ORIGINAL a times square0 := mul(15, 1)
After
Rate quadratic ORIGINAL a times square0 = 15
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S004
Before
Rate quadratic ORIGINAL endpoint0 plus k := sum(15, 2)
After
Rate quadratic ORIGINAL endpoint0 plus k = 17
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S005
Before
Rate quadratic ORIGINAL displacement1 := sub(17, 2)
After
Rate quadratic ORIGINAL displacement1 = 15
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S006
Before
Rate quadratic ORIGINAL square1 := mul(15, 15)
After
Rate quadratic ORIGINAL square1 = 225
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S007
Before
Rate quadratic ORIGINAL a times square1 := mul(15, 225)
After
Rate quadratic ORIGINAL a times square1 = 3375
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S008
Before
Rate quadratic ORIGINAL endpoint1 plus k := sum(3375, 2)
After
Rate quadratic ORIGINAL endpoint1 plus k = 3377
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S009
Before
source roles = [15, 2, 2, 1, 17]
After
derived = [[17, 3377], dy=a*(x1-x0)*(x1+x0-2h)]
Conditions: none
Use the WHOLE vertex-form quadratic.The k terms cancel and the square difference factors as(x1-x0)(x1+x0-2h).Symmetric endpoints can give dy=0 although a is nonzero;the function need not be constant.
Rule: Rate_WHOLE_quadratic_difference_of_squares · Uses: G001, S010
Before
Rate ORIGINAL y1 minus y0 := sub(3377, 17)
After
Rate ORIGINAL y1 minus y0 = 3360
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S011
Before
Rate ORIGINAL dy over dx := div(3360, 16)
After
Rate ORIGINAL dy over dx = 210
Conditions: none
Perform exact rational arithmetic on the ORIGINAL roles.SAFE bounds raw inputs only;derived integers are unbounded and never approximated by floats.
Rule: exact_rational_arithmetic · Uses: G001, S012
Before
source roles = [1, 17, 17, 3377, 16, 3360]
After
derived = [210/1]
Conditions: none
Keep the SAME endpoint orientation:(y1-y0)/(x1-x0).Both differences may reverse together,not just one.The result may be negative or0;normalize a positive denominator and retain/1.This finite endpoint rate is not a general derivative certificate.
Rule: Rate_oriented_quotient_reverse_BOTH_differences · Uses: G001, S013
S014 · premise_and_result_audit — Reverse-check EACH original datum and premise,retaining indices,signs and strict/non-strict boundaries.A correct final answer cannot replace the derivation obligations.This is candidate teaching/exact checking,not formal proof or publication clearance.S013 · premise_and_result_audit — Recompute Rate ORIGINAL dy over dx with exact rational arithmetic, not rounded decimals.S012 · premise_and_result_audit — Recompute Rate ORIGINAL y1 minus y0 with exact rational arithmetic, not rounded decimals.S011 · premise_and_result_audit — Reverse-check EACH original datum and premise,retaining indices,signs and strict/non-strict boundaries.A correct final answer cannot replace the derivation obligations.This is candidate teaching/exact checking,not formal proof or publication clearance.S010 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL endpoint1 plus k with exact rational arithmetic, not rounded decimals.S009 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL a times square1 with exact rational arithmetic, not rounded decimals.S008 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL square1 with exact rational arithmetic, not rounded decimals.S007 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL displacement1 with exact rational arithmetic, not rounded decimals.S006 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL endpoint0 plus k with exact rational arithmetic, not rounded decimals.S005 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL a times square0 with exact rational arithmetic, not rounded decimals.S004 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL square0 with exact rational arithmetic, not rounded decimals.S003 · premise_and_result_audit — Recompute Rate quadratic ORIGINAL displacement0 with exact rational arithmetic, not rounded decimals.S002 · premise_and_result_audit — Recompute Rate ORIGINAL x1 minus x0 with exact rational arithmetic, not rounded decimals.S001 · premise_and_result_audit — Reverse-check EACH original datum and premise,retaining indices,signs and strict/non-strict boundaries.A correct final answer cannot replace the derivation obligations.This is candidate teaching/exact checking,not formal proof or publication clearance.210/1
The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.
Review date: 2026-10-26
Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.
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