Question

By using suitable identities, evaluate the following:
(997)square

Answer 1

Dear student
$$\begin{gathered} {997}^2 \\ ={\left(1000-3\right)}^2 \\ ={1000}^2+3^2-2\left(1000\right)\left(3\right)\left[\because {\left(\mathrm{a}-\mathrm{b}\right)}^2={\mathrm{a}}^2+{\mathrm{b}}^2-2\mathrm{ab}\right] \\ =1000000+9-6000 \\ =99401 \end{gathered}$$
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