Guest

If the length of diagonal of regular pentagon is b and side length is a,prove that a^2/b^2+b^2/a^2=3 ???


 


If the length of diagonal of regular pentagon is b and side length is a,prove that


 


a^2/b^2+b^2/a^2=3  ???




 


Grade:10

1 Answers

Shyama P
35 Points
10 years ago

consider right triangle AOB

angle OAB =54 degree

sin54=b/2a

b=2asin54

sub in eq.

a2/(4a2sin254) + (4a2sin254)/a2 =3

Think You Can Provide A Better Answer ?

Provide a better Answer & Earn Cool Goodies See our forum point policy

ASK QUESTION

Get your questions answered by the expert for free