Cho \(P=\left(x+y\right)^2+\left(y+z\right)^2+\left(x+z\right)^2\)
\(Q=\left(x+y\right)\left(y+z\right)+\left(y+z\right)\left(z+x\right)+\left(z+x\right)\left(x+y\right)\)
CMR : Nếu P=Q thì x=y=z
phân tích đa thức thành nhân tử;
a)\(x\left(y^2+z^2\right)+y\left(z^2+x^2\right)+z\left(x^2+y^2\right)+2abc\)
b)\(\left(x+y\right)\left(x^2-y^2\right)+\left(y+z\right)\left(y^2-z^2\right)+\left(z+x\right)\left(z^2-x^2\right)\)
a) \(\left(x+a\right)\left(x+2a\right)\left(x+3a\right)\left(x+4a\right)+a^4\)
b)\(\left(x^2+y^2+z^2\right)\left(x+y+z\right)^2+\left(xy+yz+zx\right)^2\)
c) A= \(2\left(x^4+y^4+z^4\right)-\left(x^2+y^2+z^2\right)^2-2\left(x^2+y^2+z^2\right)\left(x+y+z\right)^2+\left(x+y+z\right)^4\)
Giải giúp mình với
CMR \(\frac{y-z}{\left(x-y\right).\left(x-z\right)}+\frac{z-x}{\left(y-z\right).\left(y-x\right)}+\frac{x-y}{\left(z-x\right).\left(z-y\right)}=\frac{2}{x-y}+\frac{2}{y-z}+\frac{2}{z-x}\)Cho a,b,c,x,y,z \(\ne\)0 và \(a+b+c=x+y+z=\frac{x}{a}+\frac{y}{b}+\frac{z}{c}\)CMR \(a^2x+b^2y+c^2z=0\)Thanks nhiều ạ
Cho\(\left(x+y\right)\left(x+z\right)+\left(y+z\right)\left(y+x\right)=2\left(z+x\right)\left(z+y\right)\)
CMR: \(x^2+y^2=2z^2\)
Phân tích đa thức thành nhân tử :
1) \(A=\left(x^2+y^2+z^2\right)\left(x+y+z\right)^2+\left(xy+yz+zx\right)^2\)
2)\(B=2\left(x^4+y^4+z^4\right)-\left(x^2+y^2+z^2\right)-2\left(x^2+y^2+z^2\right)\left(x+y+z\right)^2+\left(x+y+z\right)^4\)
3)\(\left(a+b+c\right)^3-4\left(a^3+b^3+c^3\right)-12abc\)
a, \(\left(x+y\right)^2+\left(x-y\right)^2\)
b, \(2\left(x-y\right).\left(x+y\right)+\left(x+y\right)^2+\left(x-y\right)^2\)
c, \(\left(x-y+z\right)^2+\left(z-y\right)^2+2\left(x-y+z\right).\left(y-z\right)\)
Tính:
\(\dfrac{x^2-yz}{\left(x+y\right)\left(x+z\right)}+\dfrac{y^2-xz}{\left(y+z\right)\left(y+x\right)}+\dfrac{z^2-xy}{\left(z+x\right)\left(z+y\right)}\)
\(\dfrac{x^2}{\left(x-y\right)\left(x-z\right)}+\dfrac{y^2}{\left(y-x\right)\left(y-z\right)}+\dfrac{z^2}{\left(z-x\right)\left(z-y\right)}\)
Tính:a) \(A=\frac{2}{x-y}+\frac{2}{y-z}+\frac{2}{z-x}+\frac{\left(x-y\right)^2+\left(y-z\right)^2+\left(z-x\right)^2}{\left(x-y\right)\left(y-z\right)\left(z-x\right)}\)
b) Cho \(\frac{x}{y+z}+\frac{y}{z+x}+\frac{z}{x+y}=1\) . Tính \(A=\frac{x^2}{y+z}+\frac{y^2}{z+x}+\frac{z^2}{x+y}\)