Question

Plzz .. Solve this no. 7 and 8

Answer 1

7. (X+1/x)^2 = x square +1/x square +2
8^2+2= x square+ 1/x square
66 = x^2+1/x^2
8.(a-1/a) ^2-2=a^2+1/a^2
5^2-2= a^2+1/a^2
23= a^2+1/a^2

Answer 2

(7)

Given equation is x + 1/x = 8.

On squaring both sides, we get

(x + 1/x)^2 = (8)^2

x^2 + 1/x^2 + 2 * x * 1/x = 64

x^2 + 1/x^2 + 2 = 64

x^2 + 1/x^2 = 64 - 2

x^2 + 1/x^2 = 62.




(8) 

Given name is a - 1/a = 5.

On squaring both sides, we get

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

a^2 + 1/a^2 - 2 * a * 1/a = 25

a^2 + 1/a^2 - 2 = 25

a^2 + 1/a^2 = 25 + 2

a^2 + 1/a^2 = 27.




Hope this helps!