MCQ
For which value of  $x$ , the function $f(x) = {x^2} - 2x$ is decreasing
  • A
    $x > 1$
  • B
    $x > 2$
  • $x < 1$
  • D
    $x < 2$

Answer

Correct option: C.
$x < 1$
c
(c) $f(x) = {(x - 1)^2} - 1$. Hence decreasing in $ x < 1.$

Aliter : $f'(x) = 2x - 2 = 2(x - 1)$

To be decreasing, $2(x - 1) < 0 \Rightarrow (x - 1) < 0 \Rightarrow x < 1$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free