Difference between revisions of "KGS math club/solution 11 20"

(Created page with "By drawing all diagonals and looking at angles we see that the triangles formed by {c, d, d} and {c, c, d-c} are similar. Then c : d = (d-c) : c After that few calculations le...")
 
 
Line 1: Line 1:
 
By drawing all diagonals and looking at angles we see that the triangles formed by {c, d, d} and {c, c, d-c} are similar.  
 
By drawing all diagonals and looking at angles we see that the triangles formed by {c, d, d} and {c, c, d-c} are similar.  
 +
 
Then c : d  =  (d-c) : c
 
Then c : d  =  (d-c) : c
After that few calculations lead to c : d = <math>(sqrt(5)-1)/2</math>
+
 
 +
After few calculations  c : d = <math>(sqrt(5)-1)/2</math>

Latest revision as of 14:24, 14 August 2012

By drawing all diagonals and looking at angles we see that the triangles formed by {c, d, d} and {c, c, d-c} are similar.

Then c : d = (d-c) : c

After few calculations c : d = $(sqrt(5)-1)/2$