Prove that a triangle is right angled if `(1-(r_(1))/(r_(2)))(1-(r_(1))/(r_(3))) = 2`

In triangle ABC,if (1-(r_(1))/(r_(2)))(1-(r_(2))/(r_(3)))=2 then the triangle is

If in a triangle (1-(r_(1))/(r_(2)))(1-(r_(1))/(r_(3)))=2 , then the triangle is

In triangle ABC,If(1-(r)/(r_(2)))(1-(r_(2))/(r_(3)))=2 then the triangle is

If in a triangle, (1-(r_(1))/(r_(2))) (1 - (r_(1))/(r_(3))) = 2 , then the triangle is

Value of 1/(r_(1)^2)+ 1/(r_(2)^2)+ 1/(r_(3)^2)+ 1/(r_()^2) is :

If in a triangle (1-(r_(1))/(r_(2)))(1-(r_(1))/(r_(3)))=2 then the triangle is right angled (b) isosceles equilateral (d) none of these

If r_1=r_2+r_3+r prove that the triangle is right angled .

In a triangle ABC,if (1)/(r_(1)^(2))+(1)/(r_(2)^(2))+(1)/(r_(3)^(2))+(1)/(r^(2))=

In triangle ABC,(r_(3)+r_(1))sqrt([(rr_(2))/(r_(3)r_(1))])=

In a triangle ABC, if (r_(1)+r_(2))(r_(2)+r_(3))(r_(3)+r_(1))4RK then k=