Question

Find the value of $(7.995)^{1/3}$ correct to four decimal places.

• A. $1.9995$
• B. $1.9996$
• C. $1.9990$
• D. $1.9991$

Answer 1

Answer: (B)

$1.9996$

Answer 2

$\left(7.995\right)^{1/3}=\left(8-0.005\right)^{1/3}$
$=2\left(1-\frac{0.005}{8}\right)^{1/3}$
$=2\left[1+\left(\frac{1}{3}\right)\left(-\frac{0.005}{8}\right)\right]=2\left[1-0.000208\right]$
$=1.9996$