Question

Find the square of $395$ using identity

Answer 1

Find the square using algebraic identity

We can write $395$ as $400-5$.

On applying the identity ${(a-b)}^2=a^2-2ab+b^2$ to find the square of $395$ , we get,

$$\begin{gathered} {\left(395\right)}^2 \\ ={(400-5)}^2 \\ ={\left(400\right)}^2-2\left(400\right)\left(5\right)+{\left(5\right)}^2 \\ =160000-4000+25 \\ =156025 \end{gathered}$$
Hence, using an identity, the square of $395$ is $156025$.