Question

if a-1/a-2=6 then show (a-2)^2-1/(a-2)^2​

Answer 1

Step-by-step explanation:

If a+a1=6 and a=0; find a2−a21 .

A

±243

B

±42

C

±242

D

±43

Easy

Answer

Correct option is

C

±242

a+a1=6

Squaring both sides,

=(a+a1)2=62

=a2+(a1)2+2(a)(a1)=36

=a2+a21+2=36

=a2+a21=34

Now,

(a−a1)2=a2+a21−2(a)(a1)

=34−2

=32

=>a−a1=±32

=±42

Now,

(a2−a21)=(a+a1)(a−a1)

=6(±4