Problem for Medium Levels
Algebra
Level
2
If x is real then minimum value of
None of these
17
12
8
5
10
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1 solution
To find to minimum value, you can put it in vertex form.
x 2 − 8 x + 1 7 = y
x 2 − 8 x + 1 6 + 1 = y
( x − 4 ) 2 = y − 1
So the vertex is (4,1)
Because the coefficient of x 2 is positive, the parabola opens upwards. Therefore, the minimum value of the equation is x=4, y=1 or 1. So the answer choice is "None of these"