AP EAMCET20227 Jul 2022Evening ShiftMathematicsProperties of TrianglesActual
Let A B C be an acute-angled triangle with area R . Then, a^2 b^2-4 R^2 + b^2 c^2-4 R^2 + c^2 a^2-4 R^2 =
Options
- Aa+b+c
- Ba^2+b^2+c^2
- Ca^2+b^2+c^2 2
- D2 (a^2+b^2+c^2 )
Correct answer
C. a^2+b^2+c^2 2
Step-by-step solution
aligned & a^2 b^2-4 R^2 = a^2 b^2-(a b c)^2 . & =a b C aligned Similarly, b^2 c^2-4 R^2 =b c A c^2 a^2-4 R^2 =c a B Given, expression aligned & =a b C+b c A+c a B & = a^2+b^2-c^2 2 + b^2+c^2-a^2 2 + c^2+a^2-b^2 2 & = a^2+b^2+c^2 2 aligned