Let $f: R→R$ be defined such that
$f(x) = 16x^2 -16x+12 $
(A) Maximum value of f(x) is 8
(B) Minimum value of f(x) is 8
(C) Minimum value of f(x) is 16
(D) No maximum value of f(x)
Choose the correct answer from the options given below :
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (B), (D) Only
$f(x)=16x^2-16x+12$
$⇒f'(x)=32x-16$
for critical points,
$(32x-16)=0$
$x=\frac{16}{32}=\frac{1}{2}$
Now,
$f''(x)=32>0$
∴ f only has minima
$f(\frac{1}{2})=16(\frac{1}{2})-16(\frac{1}{2})+12$
$=8$