Question

if a-1/a =3 find a^2 +3a +1/a^2 - 3/a​

Answer 1

Answer:

For solving this, we aim in factorising in terms of a- 1/a

Coming to the equation, let's group the terms a^2, 1/a^2 as one and 3a, 3/a as another

The equation can be written as

a^2+1/a^2+3a-3/a

(a-1/a)^2 +2*a*1/a + 3*(a-1/a)

Putting the value of a-1/a =3

3^2 +2+3*3

9+2+9

20

The required answer is 20