The radius of the incircle of the equilateral triangle having

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The radius of the incircle of the equilateral triangle having each side 6 cm is

1. 2√3cm
2. √3 cm
3. 6√3 cm
4. 2 cm

Correct Option: B

On the basis of given question , we draw a figure

E = In-centre, AD ⊥ BC
AB = 6 cm, BD = 3 cm
∠ ADB = 90°
∴ AD = √AB² - BD²
AD = √6² - 3²
AD = √36 - 9
AD = √27
AD = 3√3 cm
∴ In-radius = ( 1/3 ) AD

In-radius =	1	× 3√3 = √3cm
	3