Question

If a + 1/a = 2√5 find the value of a - 1/a​

Answer 1

Answer:

(a +1/a )^2 =

(a+1/a)^2 - (a -1/a)^2 = 4 (a*1/a)

(a+1/a)^2 - (√5)^2 = 4

(a+1/a)^2 - 5=4

(a+1/a)^2 =5+4

(a+1/a)^2 = 9

(a+1/a) = √9

= 3 - ( Answer )

Answer 2

Step-by-step explanation:

(a+1/a)^2 - (a-1/a)^2 = 4

2√5 - (a-1/a)^2 = 4

2√5 - 4 = (a-1/a)^2

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AFTER THIS I DON'T KNOW

THANK YOU!!!