Hello zacharyrodThis is all to do with the Golden Ratio.
In the diagram, let . Then (since 's and are isosceles). Therefore .
Now use the fact that the 's and are similar:and now
, taking the positive root
Grandad
Hello zacharyrodThis is all to do with the Golden Ratio.
In the diagram, let . Then (since 's and are isosceles). Therefore .
Now use the fact that the 's and are similar:and now
, taking the positive root
Grandad