Difference between minimum points and values of a parabola (C1)

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jojo55
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Hi .

I am answering the below past exam question.
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For part (b) I have found the minimum point to be (1.5, 1.75) or in fractional form (3/2, 7/4).

The answer says it is just 1.75

I don't understand how this is the minimum value. I would get if it asked for the minimum y value but I am stumped as to why it would not be 1.5 (the x-value as it is lower).

Could someone please clear this up?

Thanks
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B_9710
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The minimum value of a curve  y=f(x) is the minimum y coordinate of the curve.
You can put in any (real) value of x you want, but you cannot possibly make the curve y have a value below 7/4 as you said (for real x).
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jojo55
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(Original post by B_9710)
The minimum value of a curve  y=f(x) is the minimum y coordinate of the curve.
You can put in any (real) value of x you want, but you cannot possibly make the curve y have a value below 7/4 as you said (for real x).
Ah thanks, that makes sense.
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Rather_Cynical
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The minimum value for x might be 1.5, but since it's asking you about the expression f(x), then you need to give the minimum value for f(x)

The curve is y = f(x), so your y-coordinate would be the minimum value you'd want.
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