Answer
$y^{2} + \frac{1}{y^{2}} -2$
Work Step by Step
$(y -\frac{1}{y})^{2}$
1. Square the first term. $(y)^{2} = y^{2}$
2. Multiply the first term and second term together. Then multiply this answer by 2. So $(y)(\frac{-1}{y})(2) = -2$
3. Square the last term. $(\frac{-1}{y})^{2} = \frac{1}{y^{2}}$
4. Add your answers from steps 1-3 to get $y^{2} + \frac{1}{y^{2}} -2$.
