f(-b/2a)=f(3)=-2*9+36-14=-18+36-14=4=maximum
2007-05-28 10:34:18
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answer #1
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answered by bruinfan 7
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Take the derivative of the function and set it equal to zero. So,
f'(x) = -4x + 12 = 0
Solving for this, you get that x = 3 at the maximum, so plug this back into your function. You get:
f(3) = -2(3)^2 + 12(3) -14 = -18+36-14 = 4.
Therefore, the maximum is 4 at x=3.
2007-05-28 17:38:06
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answer #2
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answered by C-Wryte 3
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- 2x^2 + 12x - 14
= -2( x^2 - 6x + 7 )
= -2( (x - 3)^2 - 2 )
= 2(2 - (x - 3)^2).
This has a maximum value of 4 when (x - 3)^2 = 0.
2007-05-28 17:55:35
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answer #3
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answered by Anonymous
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4
2007-05-28 17:33:42
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answer #4
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answered by Anonymous
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maximum (and minimum) values can be found using the first derivitive set equal to 0.
taking the first derivitive, we get
f '(x) = -4x + 12
set that = 0 and solve for x and we get
-4x = -12
x = 3
now we take that three and plug it back into the function to get the maximum value
-2(3)^2 + 12(3) - 14 =
-18 + 36 - 14 = 36 - 32 = 4
the maximum value of the above function is 4.
2007-05-28 17:36:23
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answer #5
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answered by Anonymous
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f(x) = -2x^2 +12x - 14
ok, so you will take the first derivative of this function which is:
f'(x) = -4x + 12
then you solve for x:
-4x + 12 = 0
-4x = -12
x = 3
then you will plug this back into the original function:
f(3) = -2(3)^2 + 12(3) -14
= -18 + 36 - 14
= 4
thus the max. value of the function is 4.
2007-05-28 17:59:48
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answer #6
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answered by mitzubishi4338 3
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dy/dx = -4x+12
Set = 0 getting x = 3
f(3) = -2(3^2) +12*3 -14
f(3) = -18 +36 -14 = 4
max value = 4
2007-05-28 17:36:57
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answer #7
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answered by ironduke8159 7
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ehm.... do derivative of that, set it to 0 and calculate the values for x
2007-05-28 17:33:38
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answer #8
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answered by nico 2
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about three... I think. I didn't do the math, I just looked at it.
2007-05-28 17:36:36
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answer #9
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answered by tokusie_kiuden 2
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