Question

(∩ ͡° ͜ʖ ͡°)⊃━炎炎炎炎炎炎炎炎

Question for maths expert......

Answer 1

a10= alpha^10 - beta^10

a8= alpha^8 - beta^8

a9= alpha^9 - beta^9

a10 -2a8/2a9= alpha^10 - beta^10 - 2alpha^8 + 2beta^8/ 2 ( alpha^9 - beta^9)

= alpha^8( alpha^2 -2) - beta^8( beta^2 - 2)/
2( alpha^9 - beta^9)

As alpha and beta are roots ofx^2 - 6x -2= 0

alpha^2 - 6 alpha -2= 0

alpha^2 -2 = 6 alpha

beta^2 - 6 beta -2 = 0

beta^2 -2= 6 beta

put in alpha^8( alpha^2 -2) - beta^8( beta^2 -2)/ 2( alpha^9- beta^9)

= alpha^8 × 6 alpha - beta^8( 6 beta)/ 2( alpha^9 - beta^9)

= 6( alpha^9 - beta^9)/ 2( alpha^9- beta^9)

=3


✌✌✌Dr.Dhruv✌✌✌✌✌

✌✌✌✌✌Senior Chairman of Resdtind ✌✌✌✌✌