Question

a分之1减一的完全平方减一等于多少

Answer 1

(1/a-1)²-1
=1/a²-2/a+1-1
=1/a²-2/a

Answer 2

(1/并笑渗绝脊升亏a-1)^2-1
=[(1/a-1)+1][(1/a-1)-1]
=1/a(1/a-2)
=(1/a)[(1-2a)/a]
=(1-2a)/a^2。