For all real values of x, the minimum value of is

Question

Philoid · Accepted Answer

Let

Then, f’(x) = 0

⇒ x² = 1

⇒ x = �1

Now,

And,

Also, f’’(-1) = -4 < 0

Then, by second derivative test, f is minimum at x = 1 and the minimum value is given by