In an equlilateral triangle, (circumradius) : (inradius) : (exradius) is equal to
1 : 1 : 1
1 : 2 : 3
2 : 1 : 3
3 : 2 : 4
The exradius =4RsinA2.cosB2.cosC2=4R.12.√32.√32=32RAlso r=4RsinA2sinB2sinC2r=R2∴R:r:extradius=R:R2:2R2⇒1:12:32 or 2:1:3
Prove that in an equilateral triangle, the circumcentre and incentre are the same. What is the ratio of the circumradius and inradius?