2025 · Q75
if 2s = a + b + c then what is:s(s - a)(s - b)(s - c) [(1)/(s-a)+(1)/(s-b)+(1)/(s-c)-(1)/(s)]
Elementary MathematicsAlgebra
- Aabc
- B2abc
- C4abc
- Dab + bc + ca
Explanation
Let Δ² = s(s−a)(s−b)(s−c). The bracket equals [s((s−b)(s−c) + (s−c)(s−a) + (s−a)(s−b)) − (s−a)(s−b)(s−c)]/[s(s−a)(s−b)(s−c)], and the numerator is identically abc, so the whole expression equals abc, option (a).