1. Define Ratios:
Let
BA′A′C=α,CB′B′A=β,AC′C′B=γ.
According to Ceva's Theorem, for the cevians AA′, BB′, and CC′ to be concurrent, the product of these ratios must be equal to 1:
αβγ=1.
2. Apply Van Aubel's Theorem:
Van Aubel's Theorem states that:
OA′AO=β+γ1,OB′BO=γ+α1,OC′CO=α+β1.
3. Sum of Ratios:
Given in the problem:
OA′AO+OB′BO+OC′CO=92.
4. Product of Ratios:
We need to find the value of:
OA′AO×OB′BO×OC′CO.
Using the expressions from Van Aubel's Theorem, we have:
OA′AO×OB′BO×OC′CO=(β+γ1)(γ+α1)(α+β1).
5. Expand the Product:
Expanding the product, we get:
(β+γ1)(γ+α1)(α+β1).
Using the identity αβγ=1, we can simplify:
(β+γ1)(γ+α1)(α+β1)=βγα+βγβ1+βα1α+γ1γα+γ1γα1+γ1β1α+γ1β1α1.
Simplifying further:
=αβγ+γ+β+α+α1+β1+γ1+αβγ1.
Since αβγ=1, we have:
=1+γ+β+α+α1+β1+γ1+1.
Combining terms:
=2+(β+γ1)+(γ+α1)+(α+β1).
Given that:
OA′AO+OB′BO+OC′CO=92,
we substitute:
=2+92=94.
The final answer is 94.