1.

The x-coordinate of the incentre of the trianglethat has the coordinates of mid points of its sides as (0, 1), (1, 1) and (1,0) is(1) `2-sqrt(2)`(2) `1+sqrt(2)`(3) `1-sqrt(2)`(4) `2+sqrt(2)`

Answer» `0 = (a+x)/2`
`x=-a`
`1= (b+y)/2`
`y= 2-b`
now,` 1= (-a + 2 -a)/2`
`2 = -2a + 2`
`a= 0`
& `4-2b = 0`
`b=2`
`AC= sqrt((0-2)^2 + (2-0)^2) = sqrt 8 `
`I_n = (ax_1 + bx_2 + c x_3)/(a+b+c)`
where, a,b,c are length of the sides & `x_1, x_2 , x_3` are opposite vertex coordinates
so,` (2 xx 2 + 2 xx 0 + sqrt8 xx 0)/(2 + 2 + sqrt8)`
`= 4/(4 + 2 sqrt2) xx (4 - 2sqrt 2)/(4 - 2sqrt 2)`
`= (16- 8 sqrt2)/(16- 8)`
`= (16- 8 sqrt2)/8`
`= (4-2sqrt2)/2 = 2 - sqrt2`
option 1 is correct


Discussion

No Comment Found

Related InterviewSolutions