Question

a=6+✓3 then find a-1/a​

Answer 1

Always remember this :

If A^m = a+√b ,then A^-m or 1/A^m =a-√b

Now coming to ur question...

a=6+√3

1/a =6-√3

So a+1/a=6+√3+6-√3

a+1/a=2(6)=12 ans