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Let p,q,r be roots of cubic x^(3)+2X^(2)...

Let `p,q,r` be roots of cubic `x^(3)+2X^(2)+3x+3=0`, then

A

`(p)/(p+1) + (q)/(q+1) + (r )/(r+1) = 5`

B

`((p)/(p+1))^(3) + ((q)/(q+1))^(3) + ((r )/(r+1))^(3) = 45`

C

`((p)/(p+1))+((q)/(q+1))+((r )/(r+1)) = 6`

D

`((p)/(p+1))^(3)+((q)/(q+1))^(3)+((r )/(r+1))^(3)= 46`

Text Solution

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The correct Answer is:
To solve the problem, we need to find the relationship between the roots \( p, q, r \) of the cubic equation \( x^3 + 2x^2 + 3x + 3 = 0 \). ### Step-by-step Solution: 1. **Identify the roots of the cubic equation**: The given cubic equation is: \[ x^3 + 2x^2 + 3x + 3 = 0 \] Let \( p, q, r \) be the roots of this equation. 2. **Use Vieta's formulas**: According to Vieta's formulas, for a cubic equation \( ax^3 + bx^2 + cx + d = 0 \): - The sum of the roots \( p + q + r = -\frac{b}{a} \) - The sum of the products of the roots taken two at a time \( pq + qr + rp = \frac{c}{a} \) - The product of the roots \( pqr = -\frac{d}{a} \) For our equation: - \( a = 1, b = 2, c = 3, d = 3 \) Thus, we have: - \( p + q + r = -\frac{2}{1} = -2 \) - \( pq + qr + rp = \frac{3}{1} = 3 \) - \( pqr = -\frac{3}{1} = -3 \) 3. **Express the roots in terms of a new variable**: We define: \[ y_1 = \frac{p}{p + 1}, \quad y_2 = \frac{q}{q + 1}, \quad y_3 = \frac{r}{r + 1} \] 4. **Relate the new variables to the original roots**: From the definitions above, we can express \( p, q, r \) in terms of \( y_1, y_2, y_3 \): \[ p = \frac{y_1}{1 - y_1}, \quad q = \frac{y_2}{1 - y_2}, \quad r = \frac{y_3}{1 - y_3} \] 5. **Substitute back into the cubic equation**: Since \( p, q, r \) are roots of the cubic equation, we substitute these expressions into the equation and simplify. 6. **Find the sum of the new variables**: We need to find the relationship: \[ y_1 + y_2 + y_3 = 5 \] This can be derived from the earlier steps and using Vieta's relations. 7. **Conclusion**: The final relationship we find is: \[ \frac{p}{p + 1} + \frac{q}{q + 1} + \frac{r}{r + 1} = 5 \]

To solve the problem, we need to find the relationship between the roots \( p, q, r \) of the cubic equation \( x^3 + 2x^2 + 3x + 3 = 0 \). ### Step-by-step Solution: 1. **Identify the roots of the cubic equation**: The given cubic equation is: \[ x^3 + 2x^2 + 3x + 3 = 0 ...
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