## WeBWorK Problems

### Context("Fraction") and FormulaUpToConstant

by Chrissy Safranski -
Number of replies: 0
Can I not use both FormulaUpToConstant for an indefinite integral and Context("Fraction") at the same time?  The only reason I'm trying to is that I would like the correct answer to display as the fraction, rather than the decimal.  I'm not trying to limit what students can enter.

If I change FormulaUpToConstant to Formula or Compute, then I don't get any errors and the display of the correct answer is what I want, but leaving it as FormulaUpToConstant gives errors from the context pl files and from the Differentiaion parser.  I really want students to practice giving the +C, so I like using FormulaUpToConstant instead of writing the +C in the text.

-----------------------------------
"PGstandard.pl",
"MathObjects.pl",
"contextFraction.pl",
$showPartialCorrectAnswers = 1; Context("Fraction"); Context()->variables->are(x=>"Real",dx=>"Real"); Context()->{error}{msg}{"Variable 'd' is not defined in this context"} = "Don't leave a space - type 'dx' (without quotes).";$a=random(2,10,1)*random(-1,1,2);
$u=Compute("x");$dvnodx = Compute("e^($a x)");$ddvnodx = $dvnodx->D->reduce;$dv = Compute("$dvnodx dx");$dunodx=$u->D;$du= Compute("$dunodx dx")->reduce;$v=Compute("1/$a* e^($a x)")->reduce;
$uv = ($u)*($v)->reduce;$vdu = $v*$du->reduce;
$ans=FormulaUpToConstant("1/$a x e^($a x)-1/($a)^2 e^(\$a x)");