کدام گزینه نادرست است؟
1 )
$\mathop {(\mathop 7\nolimits^{ - 2} )}\nolimits^0 = 1$
2 )
$\mathop {(\mathop 2\nolimits^3 )}\nolimits^{ - 4} = \mathop 2\nolimits^{ - 12} $
3 )
$\mathop 4\nolimits^{ - 1} = {1 \over 4}$
$\mathop 3\nolimits^{ - 2} = - 9$