DraggableProofs

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Using Draggable Statements

This PG code shows how develop a proof with random statements that need to go in the correct order.

• PGML location in OPL: FortLewis/Authoring/Templates/Misc/DraggableProof_PGML.pg

Problem Techniques Index

PG problem file	Explanation
DOCUMENT(); loadMacros( 'PGstandard.pl', 'MathObjects.pl', 'PGML.pl', 'draggableProof.pl', 'PGcourse.pl' ); TEXT(beginproblem());	Details of the draggableProof.pl macro can be found in [the POD].
$statements = [ 'Assume \(\sqrt{2}=\frac{a}{b}\) where \(a,b\) are integers, with \(\text{gcd}(a,b)=1\) ', '\(2 = \frac{a^2}{b^2}\)', '\(a^2 = 2b^2\)', 'if \(a^2\) is even, then \(a\) must be even', 'Let \(a=2k\) for \(k\) some integer', 'We can then write \( 2 = \frac{4k^2}{b^2}\) or \(b^2 = 2k^2\)', 'Therefore \(b^2\) is even, so \(b\) is also even', 'If \(a\) and \(b\) are both even, then the initial assumption that \(\text{gcd}(a,b)=1\) is contradicted.', '\(\sqrt{2}\) is therefore not rational.' ]; # These are extra statements that are not needed. $extra = [ 'Then \(a\) is odd', '\(b^2\) cannot be rational.', 'therefore \(a = 2b\)' ]; $proof = DraggableProof( $statements, $extra );	The DraggableProof function takes an arrayref of correct statements, followed (optionally) by extra statements. See the POD for more options.
BEGIN_PGML [@ $proof->Print @]* END_PGML
ANS($proof->cmp);	Answer Evaluation:
BEGIN_PGML_SOLUTION Solution explanation goes here. END_PGML_SOLUTION COMMENT('Allows integration in either order. Uses PGML.'); ENDDOCUMENT();	Solution:

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Problem Techniques Index

• POD documentation: draggableProof.html