Question

if a-1/a=2 find what is the value of a^2-1/a^2?

Answer 1

Step-by-step explanation:

=> a-1/a=2

=> a-1=2a

=> a=-1

a^2-1/a^2 will be

=> (-1) ^2-1/(-1)^2

=> 0

Answer 2

Answer:

Given,

a-1/a=2

We know that

(a-1/a)²=a²+1/a²-2

2²=a²+1/a²-2

4+2=a²+1/a²

a²+1/a²=6

now

(a+1/a)²=a²+1/a²+2

(a+1/a)²=6+2

a+1/a=√8

a+1/a=2√2

now we know that

(a+1/a)(a-1/a)=a²-1/a²

2×2√2=a²-1/a²

a²-1/a²=4√2