Question

if a=3+2√2 find the value of a^2+1/a^2

Urgent i need in 2 mins

Answer 1

a^2+1/a^2

We know that (x^2+2×x×y+y^2)

=(x+y)^2

now, let x be a and y be 1/a

So,.

a^2+1/a^2=(a)^2+(1/a)^2

now add 2xy i.e.2×a×1/a=2( since a gets cancelled out)

now

so,..........