x = 2 lx - 1l + lx - 3l =

x = 2 lx - 1l + lx - 3l =

lx - 1l + lx - 3l
= l 2 - 1 l + l 2 - 3 l
= | 1 + | - 1 |
= 1 + 1
= 2