SOLUTION: The function f(x)=x^2-10x+21 has a maximum value or a minimum value and determine the value.

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Question 1032259: The function f(x)=x^2-10x+21 has a maximum value or a minimum value and determine the value.
Found 2 solutions by adunbar, stanbon:
Answer by adunbar(3) About Me  (Show Source):
You can put this solution on YOUR website!
The function has f'(x) = 2x-10 = 0 at the maximum / minimum point.
That means, 2x = 10 so x = 5, hence, y = 5^2 - 10*5 + 21 = 25-50+21 = -4
The max / min is at (5, -4)
f''(x) = 2 > 0 Therefore is a minimum

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The function f(x)=x^2-10x+21 has a maximum value or a minimum value and determine the value.
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Since the coefficient of x^2 is positive, f(x) has a minimum value.
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Min occurs when x = -b/(2a) = 10/(2) = 5
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Max value = f(5) = 25 - 50 + 21 = -4
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graph%28400%2C400%2C-10%2C10%2C-10%2C10%2Cx%5E2-10x%2B21%29
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Cheers,
Stan H.
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