\(2bc+b^2+c^2-a^2\)
\(=\left(b+c\right)^2-a^2\)
\(=\left(b+c+a\right)\cdot\left(b+c-a\right)\)
\(=2p\cdot\left(2p-a-a\right)\)
\(=4p\left(p-a\right)\)
\(2bc+b^2+c^2-a^2\)
\(=\left(b+c\right)^2-a^2\)
\(=\left(b+c+a\right)\cdot\left(b+c-a\right)\)
\(=2p\cdot\left(2p-a-a\right)\)
\(=4p\left(p-a\right)\)
Cho a + b + c = 2p. C/minh đẳng thức: \(2bc+b^2+c^2-a^2=4p\left(p-a\right)\)
cho a+b+c=2p
chứng minh rằng 2bc+ b2+c2- a2 = 4p(p- a)
Cho a+b+c=2p
Chứng minh rằng : 2bc + b2 +c2 -a2 =4p (p-a )
cho a+b+c = 2p .Chứng minh rằng 2bc+b2 + c2 - a2 = 4p(p-a)
Cho a+b+c=2p
CMR : 2bc \(+b^2+c^2-a^2=4p\left(p-a\right)\)
1. Cho a+ b + c = 0 . Chứng minh rằng M = N =P
với M =a ( a+b)(a+c)
N= b(b+c)(a+b)
P = c(c+a)c+b)
2. cho a+b+c = 2p .Chứng minh rằng 2bc+b2 + c2 - a2 = 4p(p-a)
Cho a + b + c = 2p
Chứng minh: 2bc + b2 + c2 - a2 = 4p.(p-a)
cho a+b+c= 2p chứng minh
2bc + b2+c2- a2 = 4p (p-a)
cho a+b+c=2p. cmr :\(2bc+b^2+c^2-a^2=4p\left(p-a\right)\)