Answers

2014-07-05T18:29:54+08:00
All right. So, it's basically in the form of (x - y)³, which if multiplied out, is equal to x³ -3x²y +3xy² - y³. 

So, we want [(a + 1) - 6]³ which, if simplied, is equal to (a - 5)³. Applying the formula, we get:

a³ -3a²(5) +3a(5)² - (5)³
a³ - 15a² + 75a - 125
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