Question

Using identity find the value
23.71*23.71-16.29*16.29/0.742

Answer 1

The given question is
$$\begin{gathered} \frac{{\left(23.71\right)}^2-{\left(16.29\right)}^2}{0.742} \\ =\frac{\left(23.71+16.29\right)\left(23.71-16.29\right)}{0.742}[\mathrm{Using}(a^2-b^2)=\left(a+b\right)\left(a-b\right)] \\ =\frac{\left(40\right)\left(7.42\right)}{0.742} \\ =\frac{40\times 742\times 1000}{742\times 100} \\ =400 \end{gathered}$$