Home
Class 9
MATHS
If x^(3) + y^(3) + z^(3) = 3xyz and x + ...

If `x^(3) + y^(3) + z^(3) = 3xyz and x + y + z = 0`, find the value of :
`((x+y)^(2))/(xy) + ((y+z)^(2))/(yz) + ((z+x)^(2))/(zx)`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we need to find the value of: \[ \frac{(x+y)^2}{xy} + \frac{(y+z)^2}{yz} + \frac{(z+x)^2}{zx} \] given that \(x^3 + y^3 + z^3 = 3xyz\) and \(x + y + z = 0\). ### Step 1: Use the identity for \(x^3 + y^3 + z^3\) From the identity, we know that: \[ x^3 + y^3 + z^3 - 3xyz = (x+y+z)(x^2 + y^2 + z^2 - xy - xz - yz) \] Since \(x + y + z = 0\), we can simplify this to: \[ x^3 + y^3 + z^3 = 3xyz \] This confirms the given condition. ### Step 2: Express \(x+y\), \(y+z\), and \(z+x\) From the equation \(x + y + z = 0\), we can express: - \(x + y = -z\) - \(y + z = -x\) - \(z + x = -y\) ### Step 3: Substitute these expressions into the original equation Now, substitute these into the expression we need to evaluate: \[ \frac{(x+y)^2}{xy} + \frac{(y+z)^2}{yz} + \frac{(z+x)^2}{zx} \] This becomes: \[ \frac{(-z)^2}{xy} + \frac{(-x)^2}{yz} + \frac{(-y)^2}{zx} \] Which simplifies to: \[ \frac{z^2}{xy} + \frac{x^2}{yz} + \frac{y^2}{zx} \] ### Step 4: Find a common denominator The common denominator for the three fractions is \(xyz\). Thus, we can rewrite the expression as: \[ \frac{z^2 \cdot z}{xyz} + \frac{x^2 \cdot x}{xyz} + \frac{y^2 \cdot y}{xyz} \] This simplifies to: \[ \frac{z^3 + x^3 + y^3}{xyz} \] ### Step 5: Use the identity again From the condition \(x^3 + y^3 + z^3 = 3xyz\), we substitute this into our expression: \[ \frac{3xyz}{xyz} = 3 \] ### Conclusion Thus, the value of the expression is: \[ \boxed{3} \]
Promotional Banner

Topper's Solved these Questions

Similar Questions

Explore conceptually related problems

If x = 2, y = 3 and z = -1, find the values of : (xy)/(z)

If x + 2y + 3z = 0 and x^(3) + 4y^(3) + 9z^(3)= 18 xyz , evaluate: ((x+2y)^(2))/(xy) + ((2y + 3z)^(2))/(yz) + ((3z+ x)^(2))/(zx)

If x = 2, y = 3 and z = -1, find the values of : (2x-3y+4z)/(3x-z)

If x=1, y=2 and z=3 , find the value of: x^3-z^3+y^3

If x-y +z = 5 and x^(2) +y^(2) +z^(2) = 49, find the value of : zx-xy -yz.

If x+y -z = 4 and x^(2) + y^(2) + z^(2) = 30 , then find the value of xy- yz- zx

If x+y+z=8\ \ a n d\ \ \ x y+y z+z x=20 , find the value of x^3+y^3+z^3-3x y z

If x^(2) + y^(2) + z^(2) - xy- yz - zx = 0 , prove that : x= y = z

If x+y+z=1,x y+y z+z x=-1 and x y z=-1, find the value of x^3+y^3+z^3dot

If x y z=0, then find the value of (a^x)^(y z)+(a^y)^(z x)+(a^z)^(x y)= (a)3 (b) 2 (c)1 (d) 0