Evaluate, Using (A + B)(A - B)= A2 - B2. 4.9 X 5.1 - Mathematics

Evaluate, using (a + b)(a - b)= a² - b².
4.9 x 5.1

Sum

4.9 x 5.1
= (5 - 0.1) x (5 + 0.1)
= (5)² - (0.1)²
= 25 - 0.01
= 24.99.

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Chapter 4: Expansions - Exercise 4.1

Chapter 4 Expansions
Exercise 4.1 | Q 6.3

Evaluate of the following:

93³ − 107³

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(4x − 5y) (16x² + 20xy + 25y²)

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\[\left( 3 + \frac{5}{x} \right) \left( 9 - \frac{15}{x} + \frac{25}{x^2} \right)\]

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\[\left( \frac{5}{x} + 5x \right)\] \[\left( \frac{25}{x^2} - 25 + 25 x^2 \right)\]

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(999)²

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999 x 1001

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