DomainRange1

Domain and Range of a Function

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This PG code shows how to evaluate answers that are inequalities which use different variables.

PG problem file	Explanation
Problem tagging data	Problem tagging:
DOCUMENT(); loadMacros( 'PGstandard.pl', 'MathObjects.pl', 'contextInequalities.pl', 'PGML.pl', 'PGcourse.pl' ); TEXT(beginproblem());	Initialization: We must load `contextInequalities.pl`.
$f = Compute('sqrt(x-4)'); Context('Inequalities-Only')->variables->are(x=>'Real'); Context()->flags->set(formatStudentAnswer=>'parsed'); $domain = Compute('x >= 4'); # the context needs to change for the range Context('Inequalities-Only')->variables->are(y=>'Real'); Context()->flags->set(formatStudentAnswer=>'parsed'); $range = Compute('y >= 0');	Setup: We specify the context in a way that requires students to enter their answer using inequalities and the variable x. If we had used `Context("Inequalities")` instead, then students would also be able to enter answers using interval notation. For more details, please see contextInequalities.pl We use `formatStudentAnswer=>'parsed'` and `Compute()` so that the student's answer are left as fractions rather than reduced to decimals. For the domain, since the variable is now `y`, we must reset the context and the variable so that students must enter the variable y in their answer.
BEGIN_PGML Suppose [` f(x) = [$f] `]. Enter inequalities for the domain and range of [` f `]. - Domain: [_______]{$domain} - Range: [_________________]{$range} [@ helpLink('inequalities') @]* END_PGML	Main Text:
BEGIN_PGML_SOLUTION Solution explanation goes here. END_PGML_SOLUTION	Solution: