In `DeltaABC,r=1, R=4, Delta=8` then the value of `ab + bc + ca =`

In Delta ABC,r=1,R=4,Delta=8 then the value of ab+bc+ca=

In Delta ABC, if r-1,R=4, Delta =8 , then ab+bc+ca=

In DeltaABC," if " A-B=120^(@) and R=8r , then the value of (1+cosC)/(1-cosC) equals : (All symbols used hav their usual meaning in a triangle)

In DeltaABC," if " A-B=120^(@) and R=8r , then the value of (1+cosC)/(1-cosC) equals : (All symbols used hav their usual meaning in a triangle)

In DeltaABC,AB=10 cm and BC=8 cm . Find the range of values that CA can take.

If ab + bc + ca = 0 , then the value of 1/(a^2 - bc) + 1/(b^2 - ca) + 1/(c^2 - ab) will be :

In DeltaABC, AB=5 cm and BC=4 cm . Find the range of value that CA can take.