Question
Use identities to evaluate : $(97)^2$
✓
Answer
$(97)^2$
$(97)^2 = (100 - 3)^2$
We know that,
$( a - b )^2 = a^2 + b^2 - 2ab$
$\therefore (100 - 3)^2$
$= 100^2 + 3^2 - 2 \times 100\times 3$
$= 10000 + 9 - 600$
$= 9,409$
$(97)^2 = (100 - 3)^2$
We know that,
$( a - b )^2 = a^2 + b^2 - 2ab$
$\therefore (100 - 3)^2$
$= 100^2 + 3^2 - 2 \times 100\times 3$
$= 10000 + 9 - 600$
$= 9,409$
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