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In an equilateral triangle show that the...

In an equilateral triangle show that the in-radius and the circum-radius are connected by `r =R/2.`

A

r=4R

B

`r=R/2`

C

`r=R/3`

D

none of these

Text Solution

Verified by Experts

We have,
`r=4RsinA/2sinB/2sinC/2`
`rArrr=4sin(3)30^(@)` `[because a=B=C=60^(@)]`
`rArrr=4R(1/8)rArrr=R/2`
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OBJECTIVE RD SHARMA ENGLISH-PROPERTIES OF TRIANGLES AND CIRCLES CONNECTED WITH THEM-Chapter Test
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