Home
Class 12
MATHS
Given a right triangle ABC with /A=90^0d...

Given a right triangle ABC with `/_A=90^0dot` Let D be the mid-point of BC. If the inradii of the triangle `A B D` and ACD are `r_1a n dr_2` then find the range of `(r_1)/(r_2)dot`

Text Solution

Verified by Experts

In the figure, D is mid-point of BC. From the geometry, `AD = BD = CD = a//2`
In `DeltaABD, r_(1) = (Delta_(1))/(s_(1))`
`rArr r_(1) = ((1)/(2) ((a)/(2))h)/(((a)/(2) + (a)/(2) c)/(2))`
`rArr r_(1) = (ah)/(2(a + c))`

In `Delta ACD, r_(2) = (Delta_(2))/(s_(2))`
`rArr r_(2) = ((1)/(2) ((a)/(2))h)/(((a)/(2) + (a)/(2) + b)/(2))`
`rArr r_(2) = (ah)/(2(a + b))`
`rArr (r_(1))/(r_(2)) = (a + b)/(a + c)`
`= (2R sin A + 2 R sin B)/(2R sin A + 2R sin C)`
`= (1 + sin B)/(1 + sin C) " " ("as " A = 90^(@))`
`= (1+ sin B)/(1+ cos B) " " ("as " C = 90^(@) - B)`
When B aproaches to `90^(@), (r_(1))/(r_(2))` approaches to 2
When B approaches to `0^(@), (r_(1))/(r_(2))` approaches to `(1)/(2)`
`:. (r_(1))/(r_(2)) in ((1)/(2), 2)`
Promotional Banner

Topper's Solved these Questions

  • PROPERTIES AND SOLUTIONS OF TRIANGLE

    CENGAGE|Exercise Exercise 5.1|12 Videos
  • PROPERTIES AND SOLUTIONS OF TRIANGLE

    CENGAGE|Exercise Exercise 5.2|8 Videos
  • PROGRESSION AND SERIES

    CENGAGE|Exercise ARCHIVES (MATRIX MATCH TYPE )|1 Videos
  • PROPERTIES OF TRIANGLE, HEIGHT AND DISTANCE

    CENGAGE|Exercise Question Bank|15 Videos

Similar Questions

Explore conceptually related problems

Given a right triangle with /_A =90^@ . Let M be the mid-point of BC. If the inradii of the triangle ABM and ACM are r_1 and r_2 then find the range of r_1/r_2

In a triangle A B C ,/_A=60^0a n db : e=(sqrt(3)+1):2, then find the value of (/_B-/_C)dot

Let A B C be a triangle with /_B=90^0 . Let AD be the bisector of /_A with D on BC. Suppose AC=6cm and the area of the triangle ADC is 10c m^2dot Find the length of BD.

In Delta ABC if r_1=2r_2=3r_3 and D is the mid point of BC then cos/_ADC=

in a triangle ABC , let angle C = (pi)/(2) if r the in radius and R is the circumradius of the triangle ABC , then 2( r+R) equals

Let ABC be a triangle with /_A=45^0dot Let P be a point on side BC with PB=3 and PC=5. If O is circumcenter of triangle ABC, then length OP is sqrt(18) (b) sqrt(17) (c) sqrt(19) (d) sqrt(15)

ABC is a right triangle , right angled at A and D is the mid point of AB . Prove that BC^(2) =CD^2 +3BD^(2) .

In Delta ABC, hat(A) =90^(@), AB = 4, AC = 3, D is the mid point of BC. Then BD is :

In triangle ABC, if r_(1) = 2r_(2) = 3r_(3) , then a : b is equal to

If z_1a n dz_2 are conjugate to each other then find a r g(-z_1z_2)dot