Question

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

Answer 1

\[y = x^2 \]
\[ ∆ x = 0 . 1\]
\[ x = 10\]
\[\frac{dy}{dx} = 2x\]
\[ \Rightarrow \left( \frac{dy}{dx} \right)_{x = 10} = 20\]
\[ \Rightarrow ∆ y = dy = \frac{dy}{dx}dx = 20 \times 0 . 1 = 2\]