If $$a, b, c$$ are the sides of a triangle, then the minimum value of $$\frac{a}{{b + c - a}} + \frac{b}{{c + a - b}} + \frac{c}{{a + b - c}}$$ is equal to
A.
3
B.
6
C.
9
D.
12
Answer :
3
Solution :
Given expression is $$\frac{1}{2}\sum {\frac{{2a}}{{b + c - a}}} $$
$$\eqalign{
& = \frac{1}{2}\sum {\left( {\frac{{2a}}{{b + c - a}} + 1} \right) - \frac{3}{2}} \cr
& = \frac{1}{2}\left( {a + b + c} \right)\sum {\frac{1}{{b + c - a}} - \frac{3}{2}} \cr
& {\text{Now, as }}\left( {a + b + c} \right) = \sum {\left( {b + c - a} \right)} \cr} $$
Applying A.M. $$ \geqslant $$ H.M.
Minimum value of the expression $$ = \frac{1}{2} \times 9 - \frac{3}{2} = 3.$$
Releted MCQ Question on Algebra >> Sequences and Series
Releted Question 1
If $$x, y$$ and $$z$$ are $${p^{{\text{th}}}},{q^{{\text{th}}}}\,{\text{and }}{r^{{\text{th}}}}$$ terms respectively of an A.P. and also of a G.P., then $${x^{y - z}}{y^{z - x}}{z^{x - y}}$$ is equal to:
If $$a, b, c$$ are in G.P., then the equations $$a{x^2} + 2bx + c = 0$$ and $$d{x^2} + 2ex + f = 0$$ have a common root if $$\frac{d}{a},\frac{e}{b},\frac{f}{c}$$ are in-