# ^.^'s question at Yahoo! Answers (Linearization)

MHB Math Helper

#### Fernando Revilla

##### Well-known member
MHB Math Helper
Hello ^.^,

Deriving: $f'(x)=\dfrac{4}{4x}=\dfrac{1}{x}$, so $f'(1/4)=\dfrac{1}{1/4}=4$. Now by definition of $L$, $$L(1/4):\mathbb{R}\to \mathbb{R}\\L(1/4)(h)=f'(1/4)h=4h$$ Or in classical notation, $L(1/4)\;(dx)=4\;dx$.

If you have further questions, you can post them in Calculus section.