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Using identify, find the value of (-7)^(...

Using identify, find the value of `(-7)^(3)+(5)^(3)+(2)^(3)`.

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To solve the problem using the identity for the sum of cubes, we will follow these steps: ### Step 1: Identify the values We are given the expression \((-7)^3 + (5)^3 + (2)^3\). Let's denote: - \(x = -7\) - \(y = 5\) - \(z = 2\) ### Step 2: Check the sum We need to check if \(x + y + z = 0\): \[ x + y + z = -7 + 5 + 2 \] Calculating this gives: \[ -7 + 5 = -2 \] \[ -2 + 2 = 0 \] Thus, \(x + y + z = 0\). ### Step 3: Apply the identity According to the identity: \[ x^3 + y^3 + z^3 = 3xyz \quad \text{(if } x + y + z = 0\text{)} \] We can now substitute \(x\), \(y\), and \(z\) into the identity: \[ (-7)^3 + (5)^3 + (2)^3 = 3 \cdot (-7) \cdot 5 \cdot 2 \] ### Step 4: Calculate \(xyz\) Now we calculate \(xyz\): \[ xyz = (-7) \cdot 5 \cdot 2 \] Calculating this step-by-step: \[ (-7) \cdot 5 = -35 \] \[ -35 \cdot 2 = -70 \] So, \(xyz = -70\). ### Step 5: Substitute back into the identity Now substituting back into the identity: \[ (-7)^3 + (5)^3 + (2)^3 = 3 \cdot (-70) \] Calculating this gives: \[ 3 \cdot (-70) = -210 \] ### Final Answer Thus, the value of \((-7)^3 + (5)^3 + (2)^3\) is: \[ \boxed{-210} \]
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CBSE COMPLEMENTARY MATERIAL-POLYNOMIALS-Part C
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  2. Factories 125x^(3)+8y^(3)+z^(3)-30xyz.

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  4. If the polynomials a x^3+4 x^2 + 3x -4 and x^3 - 4x + a leave the sam...

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  5. If ((9)/(10))^(3) -(2/5)^(3)-(1/2)^(3)=(x)/(50), find x

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  6. If (x-3) and (x-1/3) are factors of the polynomial px^(2)+3x+r, show t...

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  7. Using identify, find the value of (-7)^(3)+(5)^(3)+(2)^(3).

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  8. Find the dimensions of cube whose volume is given by the expression. 4...

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  9. Given possible expression for the length and breadth of each of the fo...

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  12. I f a+b+c=0,f i n d t h e v a l u e((b+c)^2)/(b c)+((c+a)^2)/(c a)+((a...

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  13. Simplify: ((a^2-b^2)^3+(b^2-c^2)^3+(c^2-a^2)^3)/((a-b^3+(b-c)^3+(c-a)^...

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  14. .Factorise: (2a-b-c)^(3)+(2b-c-a)^(3)+(2c-a-b)^(3)

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  15. If the polynomial 4x^(3)-16x^(2)+ax+7 is exactly divisible by x-1, the...

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  16. If p,q & r are all non zero and p+q+r=0, prove that p^(2)/(qr)+(q^(2))...

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  17. Factories 9x^(3)-27x^(2)-100x+300

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  18. If (x+4) is a factor of the polynomial x^(3)-x^(2)-14x+24, find the ot...

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  19. x/y+y/x=-1( w h e r e ,x , y!=0) then find the value of x^3-y^3

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