Simplify Using Following Identity : ( a +- B )(A^2 +- Ab + B^2) = A^3 +- B^3 ( 3x - 5/X )( 9x^2 + 15 + 25/X^2) - Mathematics

Simplify using following identity : `( a +- b )(a^2 +- ab + b^2) = a^3 +- b^3`
`( 3x - 5/x )( 9x^2 + 15 + 25/x^2)`

Sum

`( 3x - 5/x )( 9x^2 + 15 + 25/x^2)`

=`( 3x - 5/x )[ (3x)^2 + (3x)(5/x) + (5/x)^2 ]`

= `(3x)^3 - (5/x)^3`

= `27x^3 - 125/x^3`

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Chapter 4: Expansions (Including Substitution) - Exercise 4 (E) [Page 66]

Chapter 4 Expansions (Including Substitution)
Exercise 4 (E) | Q 2.2 | Page 66

Simplify : ( x - 6 )( x - 4 )( x + 2 )

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