Question
Simplify the following using the identities: $178 × 178 - 22 × 22$
✓
Answer
$178 × 178 - 22 × 22$
Let us consider the following expression:
Using the identity $(a + b) (a - b) = a^2 - b^2$
$178 × 178 - 22 × 22$
$= 178^2- 22^2$
$= (178 + 22)(178 - 22)$
$= 200 × 156$
$= 31200$
Thus, the answer is $31200.$
Let us consider the following expression:
Using the identity $(a + b) (a - b) = a^2 - b^2$
$178 × 178 - 22 × 22$
$= 178^2- 22^2$
$= (178 + 22)(178 - 22)$
$= 200 × 156$
$= 31200$
Thus, the answer is $31200.$
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