Question

if a=2+√3,find a - 1÷a

Answer 1

Answer:

a=2+√3

1/a=1/(2+√3)

=(2-√3)/(2+√3)(2-√3)

=(2-√3)/(2^2-√3^2)

=(2-√3)/(4-3)

=2-√3

a-1/a=(2+√3)-(2-√3)=2+√3-2+√3=2√3