S001 · implies
Before
(g∘f)(x)
After
g(f(x)):apply f first,then g
Conditions: none
The function on the right acts first;composition is not multiplication of two function values.
Step identifiers and dependencies
Rule: composition_order · Uses: G001
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← Question derivation index · Original question batch
R0005-03045 · q-20260930-r04-composition-affine-evaluation-0020
Let f:R→R be f(t)=(2)t+(7) and g:R→R be g(t)=(2)t+(0). Find (g∘f)(7) exactly.
G001 — Let f:R→R be f(t)=(2)t+(7) and g:R→R be g(t)=(2)t+(0). Find (g∘f)(7) exactly.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
(g∘f)(x)
After
g(f(x)):apply f first,then g
Conditions: none
The function on the right acts first;composition is not multiplication of two function values.
Rule: composition_order · Uses: G001
Before
f(x) product := mul(2, 7)
After
f(x) product = 14
Conditions: none
Substitute the current input and multiply by the coefficient.
Rule: exact_rational_arithmetic · Uses: G001, S001
Before
f(x) value := sum(14, 7)
After
f(x) value = 21
Conditions: none
Then add this function's own constant term.
Rule: exact_rational_arithmetic · Uses: G001, S002
Before
g(f(x)) product := mul(2, 21)
After
g(f(x)) product = 42
Conditions: none
Substitute the current input and multiply by the coefficient.
Rule: exact_rational_arithmetic · Uses: G001, S003
Before
g(f(x)) value := sum(42, 0)
After
g(f(x)) value = 42
Conditions: none
Then add this function's own constant term.
Rule: exact_rational_arithmetic · Uses: G001, S004
S005 · premise_and_result_audit — Recompute g(f(x)) value with exact rational arithmetic, not rounded decimals.S004 · premise_and_result_audit — Recompute g(f(x)) product with exact rational arithmetic, not rounded decimals.S003 · premise_and_result_audit — Recompute f(x) value with exact rational arithmetic, not rounded decimals.S002 · premise_and_result_audit — Recompute f(x) product with exact rational arithmetic, not rounded decimals.S001 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.42
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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