Evalute : ((2x)/7 - (7y)/4)^2 - Mathematics

Evalute : `((2x)/7 - (7y)/4)^2`

Sum

`((2x)/7 - (7y)/4)^2`

We know that
( a - b )² = a² - 2ab + b²

∴ `((2x)/7 - (7y)/4)^2 = ((2x)/7)^2 + ((7y)/4)^2 - 2 xx (2x)/7 xx (7y)/4`

= `(4x^2)/(49) + (49y^2)/16 - xy`

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Chapter 4: Expansions (Including Substitution) - Exercise 4 (A) [Page 57]

Chapter 4 Expansions (Including Substitution)
Exercise 4 (A) | Q 3.2 | Page 57

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