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Factoring a sum or difference of two cubes

Factoring a sum or difference of two cubes-example-1
User Randy Hall
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1 Answer

4 votes

Answer:

(5 + 2y)(25 - 10y + 4y²)

Explanation:

given

125 + 8y³ ← is a sum of cubes and factors in general as

a³ + b³

= (a + b)(a² - ab + b² )

then

125 + 8y³

= 5³ + (2y)³ ← with a = 5 and b = 2y

= (5 + 2y)(5² - 5(2y) + (2y)² )

= (5 + 2y)(25 - 10y + 4y² ) ← in factored form

User Aaron Hall
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