Question

if a^2+1/a^2=5. evaluate a^4+1/a^4​

Answer 1

>(a^4+1/a^4)

>(a^2+1/a^2)^2-1 [a^2+b^2=(a+b)^2-2ab]

>(5)^2 - 1

>24

Therefore, 24 is the answer.