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प्रश्न
Simplify the following using the formula: (a − b)(a + b) = a2 − b2: (79)2 − (69)2
उत्तर
Here, we will use the identity \[(a - b)(a + b) = a^2 - b^2\]
Let us consider the following expression:
\[\left( 79 \right)^2 - \left( 69 \right)^2 \]
\[ = \left( 79 + 69 \right)\left( 79 - 69 \right)\]
\[ = 148 \times 10\]
\[ = 1480\]
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