Question

If $f\left(x\right)=\frac{x^2}{2}+3x$ where $x=2,\delta x=0.05$ then $df=?$

• A. $2.5$
• B. $0.25$
• C. $2.635$
• D. $2.652$

Answer 1

The correct option is B $0.25$

$f\left(x\right)=\frac{x^2}{2}+3x$

$df=(\frac{2x}{2}+3)\delta x$

$df=(x+3)\delta x$

$df=(2+3)\left(0.05\right)$

$df=0.25$

$\therefore$ Answer : option $\left(B\right)$