Evalute : ( 7/8x + 4/5y)^2

Evalute : `( 7/8x + 4/5y)^2`

Sum

`( 7/8x + 4/5y)^2`

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

∴ `( 7/8x + 4/5y)^2`

= `(7/8x)^2 + (4/5y)^2 + 2 xx 7/8x xx 4/5y`

= `(49x^2)/(64) + (16y^2)/25 + (7xy)/5`

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

Chapter 4 Expansions (Including Substitution)
Exercise 4 (A) | Q 3.1 | Page 57

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