What is the expansion of $(1-\frac{1}{p})^2$ ?

$ 1+\frac{2}{p} -\frac{1}{p^2}$ $ 1-\frac{2}{p} +\frac{1}{p^2}$ $ 1-\frac{2}{p} -\frac{1}{p^2}$ $ 1+\frac{2}{p} +\frac{1}{p^2}$

$ 1-\frac{2}{p} +\frac{1}{p^2}$

( a - b )2 = a2 + b2 - 2ab  $(1-\frac{1}{p})^2$ = 12 + \(\frac{1}{p^2}\) - 2 × 1 × \(\frac{1}{p}\) =  $(1-\frac{1}{p})^2$ = $ 1-\frac{2}{p} +\frac{1}{p^2}$