If $x+y+z = 0$ show that $x^{3}+y^{3}+z^{3}=3xyz$
Given: If $x+y+z = 0$
To find: Show that $x^{3}+y^{3}+z^{3}=3xyz$
Solution:
We know that,
=$x^{3}+y^{3}+z^{3}-3xyz=(x+y+z)(x^{2}+y^{2}+z^{2}-xy-yz-zx)$
Putting $x+y+z =0$
$x^{3}+y^{3}+z^{3}-3xyz= (0)(x^{2}+y^{2}+z^{2}-xy-yz-zx)$
$x^{3}+y^{3}+z^{3}-3xyz=0$
$x^{3}+y^{3}+z^{3}=3xyz$
- Related Articles
- If \( x+y+z=0 \), show that \( x^{3}+y^{3}+z^{3}=3 x y z \).
- If \( 3^{x}=5^{y}=(75)^{z} \), show that \( z=\frac{x y}{2 x+y} \).
- Verify that \( x^{3}+y^{3}+z^{3}-3 x y z=\frac{1}{2}(x+y+z)\left[(x-y)^{2}+(y-z)^{2}+(z-x)^{2}\right] \)
- If $x + y + z = 8$ and $xy + yz+ zx = 20$, find the value of $x^3 + y^3 + z^3 – 3xyz$.
- If \( 2^{x}=3^{y}=6^{-z} \), show that \( \frac{1}{x}+\frac{1}{y}+\frac{1}{z}=0 \).
- Factorise : \( 27 x^{3}+y^{3}+z^{3}-9 x y z \)
- If \( 2^{x}=3^{y}=12^{z} \), show that \( \frac{1}{z}=\frac{1}{y}+\frac{2}{x} \).
- Simplify:$2 x+3 y-4 z-(3 y+5 x-2 z)$
- Subtract $3 x y+5 y z-7 z x$ from $5 x y-2 y z-2 z x+10 x y z$.
- Show that:\( \left(\frac{a^{x+1}}{a^{y+1}}\right)^{x+y}\left(\frac{a^{y+2}}{a^{z+2}}\right)^{y+z}\left(\frac{a^{z+3}}{a^{x+3}}\right)^{z+x}=1 \)
- If $2^x \times 3^y \times 5^z = 2160$, find $x, y$ and $z$. Hence, compute the value of $3^x \times 2^{-y} \times 5^{-z}$.
- Factorize each of the following expressions:\( \frac{1}{27} x^{3}-y^{3}+125 z^{3}+5 x y z \)
- Factorize each of the following expressions:\( \left(\frac{x}{2}+y+\frac{z}{3}\right)^{3}+\left(\frac{x}{3}-\frac{2 y}{3}+z\right)^{3} +\left(-\frac{5 x}{6}-\frac{y}{3}-\frac{4 z}{3}\right)^{3} \)
- Find the following products:\( \frac{-8}{27} x y z\left(\frac{3}{2} x y z^{2}-\frac{9}{4} x y^{2} z^{3}\right) \)
- Verify associativity of addition of rational numbers i.e., $(x + y) + z = x + (y + z)$, when:(i) \( x=\frac{1}{2}, y=\frac{2}{3}, z=-\frac{1}{5} \)(ii) \( x=\frac{-2}{5}, y=\frac{4}{3}, z=\frac{-7}{10} \)(iii) \( x=\frac{-7}{11}, y=\frac{2}{-5}, z=\frac{-3}{22} \)(iv) \( x=-2, y=\frac{3}{5}, z=\frac{-4}{3} \)
Kickstart Your Career
Get certified by completing the course
Get Started