Question 1192303
<pre>

{{{y = 4x^2-x-4}}}

{{{dy/dx=8x-1}}}

{{{dy=(8x-1)dx}}}

x = 2, dx = &Delta;x = 0.02

{{{dy=(8*2-1)*0.02}}}

{{{dy=0.3}}}

dy is approximately &Delta;y, so

the fractional change is approximately 
0.3/2 = 0.15 which equals the approximate
percentage change, 15%.

Edwin</pre>