Question

A regular octagon is formed by cutting congruent isosceles right-angled triangles from the corners of a square. If the square has side-length 1, the side-length of the octagon is-
A. `(sqrt2-1)/(2)`
B. `sqrt2-1`
C. `(sqrt5-1)/(4)`
D. `(sqrt5-1)/(3)`

Answer 1

Correct Answer - B

Here `2((1-x^(2))/(2))=x^(2)`
`(1-x)^(2)=2x^(2)` `x=sqrt2-1`