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Element pl-order-blocks: DAG grading for proofs

This question illustrates the grading-method="dag" mode of pl-order-blocks, which is especially useful for constructing mathematical proofs.

Prove that $A \land B \land C \rightarrow A \land C$

This example uses the attribute grading-method="dag" to accept any valid topological ordering. The depends attribute on each block specifies which other blocks must appear before it.

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Correct answer

Correct answer (there may be other correct orders):

Assume $A \land B \land C$.
Then $A$ is true.
Then $C$ is true.
Since $A$ and $C$, we know $A \land C$

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Question

QID:

element/orderBlocksDag

Title:

Element pl-order-blocks: DAG grading for proofs

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Started at:

2026-08-04 20:43:31 (CDT)

Duration:

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      "ranking": -1,
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