Question

if x=2-√5 find the value of x²+1/x²​

Answer 1

Answer:

x=2-√5

(2-√5)²+ 1.

(2-√5)²

(2-√5)²= 2²-2(2√5)+1²=>4-4√5+1

=>5-4√5

5-4√5 + 1.

1 5-4√5

5-4√5 × 5-4√5

1. 5-4√5

(5-4√5)²

5-4√5

5²-2(5×4√5)+(4√5)²

5-4√5

25-2(20√5)+(16×5)

5-4√5

25-40√5+80

5-4√5

105-40√5

5-4√5

=> 21-10

1

=> 11=> ans

idk why those btches even answer, if they don't know