WAEC - Further Mathematics (2015 - No. 31)
Given that \(y = 4 - 9x\) and \(\Delta x = 0.1\), calculate \(\Delta y\).
9.0
0.9
-0.3
-0.9
คำอธิบาย
\(y = 4 - 9x\)
\(\frac{\mathrm d y}{\mathrm d x} = \frac{\Delta y}{\Delta x} = -9\)
\(\frac{\Delta y}{0.1} = -9 \implies \Delta y = -9 \times 0.1 = -0.9\)