If p and q are the roots of the equation x^2 + px + q = 0 , then

Question

A. p = 1, q = − 2
B. p = 0, q = 1
C. p = −2, q = 0
D. p = −2, q = 1
E. p = -1, q = -2

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nick1816 · Answer

p*q = q

q(p-1) = 0

q=0 or p=1

Also, p+q=-p

q= -2p

(1) when q=0, p=0

(2) when p=1, q= -2 (Option A)

Raksat · Answer

For an equation , a^2+bx+c=0
sum of roots = -b/a product of roots = c/a
Hence here
p+q =-p
pq=q
solving we will get 
p=0, q=0,

p=1, q= -2

Hence option A

fireagablast · Answer

for A
x^2 + px + q = 0 --->p=1, q=-2
x^2 + 1 -2 = (x+2)(x-1) --> roots at -2 and 1 when p=1 and q=-2

also:
sum of roots =-b/a --> a = 1, b = p
sum of roots = p+q = -b/a = -p/1
p+q = -p

1+-2 = -1 --> only option A works

shameekv1989 · Answer

If p and q are the roots of the equation x^2 + px + q = 0 , then

A. p = 1, q = − 2 
B. p = 0, q = 1 
C. p = −2, q = 0 
D. p = −2, q = 1
E. p = -1, q = -2

Sum of the roots :- p+q = -p
Product of the roots :- pq = q => p=1

Answer A :- p=1; q=-2

MathRevolution · Answer

If p and q are the roots of the equation x^2 + px + q = 0 , then

Sum of the roots: p + q = -p => -2p = q

Product of the roots: pq = q => p * -2p = -2p => p = 1. Therefore, q = -2p = -2(1) = -2

p = 1 and q = -2

Answer A

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If p and q are the roots of the equation x^2 + px + q = 0 , then

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If p and q are the roots of the equation x^2 + px + q = 0 , then

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