Ex 8.4, 1 (iii) - Chapter 8 Class 8 Algebraic Expressions and Identities

Last updated at April 18, 2024 by

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Ex 8.4, 1 Multiply the binomials. (iii) (2.5𝑙 – 0.5𝑚) and (2.5𝑙 + 0.5𝑚) (2.5𝑙 – 0.5𝑚)(2.5𝑙 + 0.5𝑚) = 2.5𝑙(2.5𝑙+0.5𝑚)−0.5𝑚(2.5𝑙+0.5𝑚) = (2.5𝑙 × 2.5𝑙)+(2.5𝑙 × 0.5𝑚)−(0.5𝑚 × 2.5𝑙)−(0.5𝑚 × 0.5𝑚) = (𝟐𝟓𝒍/𝟏𝟎×𝟐𝟓𝒍/𝟏𝟎)+(𝟐𝟓𝒍/𝟏𝟎×𝟓𝒎/𝟏𝟎)−(𝟓𝒎/𝟏𝟎×𝟐𝟓𝒍/𝟏𝟎)−(𝟓𝒎/𝟏𝟎×𝟓𝒎𝒍/𝟏𝟎) = 625/100×(𝑙 × 𝑙)+125/100 (𝑙 × 𝑚)−(125/100)×(𝑚 × 𝑙)−(25/100)×(𝑚 × 𝑚) = 6.25𝑙^2+1.25𝑙𝑚−1.25𝑙𝑚−0.25𝑚^2 = 𝟔.𝟐𝟓𝒍^𝟐−𝟎.𝟐𝟓𝒎^𝟐

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