Find a parabola with equation y=ax^2+bx+c that has a slope 10 at x=1, slope -26 at x=-1, and passes through the point (2,29)
1 answer:
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Answer:
y = 9x^2 -8x +9
Step-by-step explanation:
The given equation has derivative ...
y' = 2ax +b
The requirements on slope give rise to two equations:
2a(1) +b = 10
2a(-1) +b = -26
Adding these equations together gives ...
2b = -16 ⇒ b = -8
Then we have ...
2a -8 = 10
a = (10 +8)/2 = 9
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The given point lets us find the constant term c.
y = 9x^2 -8x +c
c = y -(9x -8)x = 29 -(9(2) -8)(2) = 29 -20 = 9
The equation of the parabola is ...
y = 9x^2 -8x +9
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