Question

For the function y = x², if x = 10 and ∆x = 0.1. Find ∆ y ?

Answer 1

\[y = x^2 \]

\[ ∆ x = 0 . 1\]

\[ x = 10\]

\[\frac{dy}{dx} = 2x\]

\[ \Rightarrow \left( \frac{dy}{dx} \right)_{x = 10} = 20\]

\[ \Rightarrow ∆ y = dy = \frac{dy}{dx}dx = 20 \times 0 . 1 = 2\]