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If p and q(ne0) are the roots of the equ...

If `p and q(ne0)` are the roots of the equation `x^(2)+px+q=0`, then the value of p must be equal to

A

a. 0, 1

B

c. `(1)/(4)`

C

b. 0

D

d. 2, 0

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The correct Answer is:
To solve the problem, we need to find the value of \( p \) given that \( p \) and \( q \) (where \( q \neq 0 \)) are the roots of the quadratic equation \( x^2 + px + q = 0 \). ### Step-by-Step Solution: 1. **Identify the coefficients**: The given quadratic equation is \( x^2 + px + q = 0 \). Here, we can identify the coefficients: - \( a = 1 \) (coefficient of \( x^2 \)) - \( b = p \) (coefficient of \( x \)) - \( c = q \) (constant term) 2. **Sum of the roots**: The sum of the roots of a quadratic equation \( ax^2 + bx + c = 0 \) is given by the formula: \[ \text{Sum of roots} = -\frac{b}{a} \] Substituting the values, we have: \[ p + q = -\frac{p}{1} = -p \] Rearranging this gives: \[ p + q = -p \implies q = -2p \quad \text{(Equation 1)} \] 3. **Substituting one root into the equation**: Since \( p \) is a root of the equation \( x^2 + px + q = 0 \), we substitute \( x = p \): \[ p^2 + p \cdot p + q = 0 \] This simplifies to: \[ p^2 + p^2 + q = 0 \implies 2p^2 + q = 0 \] 4. **Substituting \( q \) from Equation 1**: Now, we substitute \( q = -2p \) from Equation 1 into the equation \( 2p^2 + q = 0 \): \[ 2p^2 - 2p = 0 \] 5. **Factoring the equation**: We can factor out \( 2p \): \[ 2p(p - 1) = 0 \] This gives us two possible solutions: \[ 2p = 0 \quad \text{or} \quad p - 1 = 0 \] 6. **Finding the values of \( p \)**: From \( 2p = 0 \): \[ p = 0 \] From \( p - 1 = 0 \): \[ p = 1 \] 7. **Conclusion**: Thus, the possible values of \( p \) are: \[ p = 0 \quad \text{or} \quad p = 1 \] ### Final Answer: The values of \( p \) must be equal to \( 0 \) and \( 1 \). ---
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ARIHANT SSC-THEORY OF EQUATIONS-EXERCISE(LEVEL 1)
  1. If p and q(ne0) are the roots of the equation x^(2)+px+q=0, then the v...

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  2. The value of p for which the sum of the squares of the roots of the eq...

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  3. If the equation x^2 +2(a+1)x+9a−5=0 has only negative root, then

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  4. The ratio of the roots of the equation ax^(2)+bx+c=0 is same as the ra...

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  5. If every pair from among the equations x^2+px+qr=0,x^2+qx+rp=0 and x...

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  6. If roots of the equation ax^2 + bx + c = 0 are alpha/(alpha-1) and (a...

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  7. Equation ax^(2)+2x+1 has one double root if :

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  8. Find the number of quadratic equations, which are unchanged by squarin...

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  9. Find the value of sqrt(6+sqrt(6+sqrt(6+...oo)))

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  10. If alpha, beta, gamma, are the roots of the equation x^(3)+3x-1=0, the...

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  11. If f(x)=(x^(2)-x+1)/(x^(2)+x+1) ,then find f(1+b)

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  12. If x= sqrt(2 +sqrt( 2 +sqrt( 2 + ...))) then rrots of x

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  13. If alpha, beta, gamma, are the roots of the equation x^(3)+3x-1=0, the...

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  14. If x^(2)-ax-21=0 and x^(2)-3ax+35=0, a gt 0 have a common root, then a...

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  15. If alpha, beta, gamma are such that alpha +beta+gamma=2, alpha^(2)+bet...

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  16. The real values of a for which the quadratic equation 2x^2-(a^(3)+8a-1...

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  17. If alpha, beta are the roots of ax^(2)+bx+c=0 and alpha+k, beta+k are ...

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  18. If alpha, beta in R, are the roots of the equation ax^(2)+bx+c=0, k in...

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  19. If the equation x^(2) + 2 (1 + k ļx +k^(2)) = 0 has equal roots, then ...

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  20. The least integral value of 'a' for which the equation x^2+2(a - 1)...

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