Question

if a =2+√3 then find the value of a-1/a
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Answer 1

Answer:

a=2+√3,

So, 1/a= 1/2+√3

using rationalisation,

1/2+√3 × 2-√3/2-√3

= 2-√3/ (2)²-(√3)²

= 2-√3/4-3= 2-√3/1 = 2-√3.

Now, a-1/a= 2+√3 - (2-√3)

= 2+√3-2+√3= 2√3