Question

The function $f(x)=x^2-2x$ is increasing in the interval

• A. $(-2,-1)$
• B. $(-1,0)$
• C. $(0,1)$
• D. $(1,2)$

Answer 1

Answer: (D)

$f^{\prime }(x)=2x-2=2(x-1)\ge 0$
if $f(x)$ is increasing
$\Rightarrow x\ge 1$.