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In exampla 27, the radius of the incircl...

In exampla 27, the radius of the incircle of `DeltaPQR`, is

A

4

B

3

C

43680

D

2

Text Solution

Verified by Experts

The correct Answer is:
D
`DeltaPQR` is isosceles triangle with `PQ=4sqrt2`, `PR=6sqrt2=QR.`
The coordinates of its incentre N are
`((4sqrt2xx9+6sqrt2xx1+6sqrt2xx1)/(4sqrt2+6sqrt2+6sqrt2),(4sqrt2xx0+6sqrt2xx2sqrt2+6sqrt2xx-2sqrt2)/(4sqrt2+6sqrt2+6sqrt2))`
or, (3, 0)
`:." In radius = MN = 2"`
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