Question

if a =9-4√5 find the value of (a-1/a)²​

Answer 1

Answer:

if a=9-4√5 ,then

(a-1/a)²

​=9-4√5-1/(9-4√5)^2

(8-4$\sqrt{5}$)/($9^{2}$-2x9x4$\sqrt{5}$)

=(8-4$\sqrt{5}$)/81-18x4$\sqrt{5}$+80

=(8-4$\sqrt{5}$)/(161-18x4$\sqrt{5}$)

Step-by-step explanation:

hope its help