Prove that the function given by f(x)=x3−3x2+3x−10 is increasing in R.
Given, f(x)=x3−3x2+3x−100
⇒f′(x)=3x2−6x+3=3(x2−2x+1)=3(x−1)2
For any xϵR,(x−1)2>0 since, a perfect square cannot be negative
Then, f′(x)>0. Hence, the given function f is an increasing function on R.