Test Section04FractionsTest

${x^2\over 1-x}+{1\over x-1} =$

$\displaystyle{{1\over x+y}\over x+y} =$

${{1\over(x+h)^2}-{1\over x^2}\over h} =$

${3\over x-4} - {2\over x+4} =$

${r-e^r\over e^{2r}} =$

${x^2-a^2\over x^2+2xa+a^2} =$

${1\over x^{-2}+y^{-2}} =$

${1\over r_1}+{1\over r_2}+{1\over r_3} =$

${3\over x+2}+{2x\over x^2-x-6} =$

The expression $y-12\over y+4$ can be written as $1 + {(\; )\over(\; )}$. What is the $(\; )\over(\; )$ term?