Given the quadratic p(x) = x2 + bx + c, if p(3) – p(2) = 7 then
p(4) – p(3) equals
(a) 9
(b) 11
(c) 14
(d) 21
(e) cannot determine from the given data.
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Quadratic
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chetanojha
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I am getting 9.
When substitute in 3 and 2 in equation
p(3) = 3^2 + b*3 + c --(1)
p(2) = 2^2 + b*3 + c --(2)
From 1 and 2 above, using equation p(3) – p(2) = 7 you get b=2
Similarly substituting 4 and 2 in the required equation with b=2 you get 9.
What is OA?
When substitute in 3 and 2 in equation
p(3) = 3^2 + b*3 + c --(1)
p(2) = 2^2 + b*3 + c --(2)
From 1 and 2 above, using equation p(3) – p(2) = 7 you get b=2
Similarly substituting 4 and 2 in the required equation with b=2 you get 9.
What is OA?
dtweah wrote:Given the quadratic p(x) = x2 + bx + c, if p(3) – p(2) = 7 then
p(4) – p(3) equals
(a) 9
(b) 11
(c) 14
(d) 21
(e) cannot determine from the given data.
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KICKGMATASS123
- Master | Next Rank: 500 Posts
- Posts: 113
- Joined: Thu Feb 26, 2009 8:13 am
- Location: New Jersey
- GMAT Score:650
I'm getting 9 as well..
You find the value of b from equations p(3) and p(2)
Then substitute this value into finding p(4)- p(3)
You find the value of b from equations p(3) and p(2)
Then substitute this value into finding p(4)- p(3)
-
artistocrat
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- Followed by:2 members
9 indeed.
p(x)=x^2+bx+c
p(3)=9+3b+c
-p(2)=4+2b+c
____________
5+b=7
b=2
p(4)=16+(4*2)+c
-p(3)=9+6+c
____________
=9
p(x)=x^2+bx+c
p(3)=9+3b+c
-p(2)=4+2b+c
____________
5+b=7
b=2
p(4)=16+(4*2)+c
-p(3)=9+6+c
____________
=9
