Question

X=2root6+5 then what is x+1/x

Answer 1

i hope this will help you

let the 2root6 = a

1/x = (a-5)/{(a+5)(a-5)}. By reciprocal method

1/x = (a-5)/{(a*a)-(5*5)} 

1/x = (a-5)/(a square - 25)

1/x = (2root6 -5)/{(4*6)-25}

1/x = 2root6 -5/(24-25) - 2root6-5/-1

1/x =-2root6+5 

x+1/x =2root6+5+(-2root+5)

x+1/x =2root6 +5 -2root6+5

x+1/x =5+5

x+1/x =10