If $x$ is real, then the minimum value of $x^2 - 8x + 17$ is
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → $1$ ##
Let $f(x) = x^2 - 8x + 17$
$∴f'(x) = 2x - 8$
So, $f'(x) = 0$ gives $x = 4$
Now, $f''(x) = 2 > 0, \forall x$
So, $x = 4$ is the point of local minima.
$∴$ Minimum value of $f(x)$ at $x = 4$,
$f(4) = 4 \times 4 - 8 \times 4 + 17 = 1$