You can
put this solution on YOUR website!
I thought maybe you'd like some explanation instead of just the answer,
which is probably in the back of your book.
(a - b)(2a³ - ab + 3b²)
Distribute each term in the first parentheses into the whole parenthesis
on the right:
a(2a³ - ab + 3b²) - b(2a³ - ab + 3b²)
Do the two resulting distributions:
2a4 - a²b + 3ab² - 2a³b + ab² - 3b³
Collect like terms in ab²
2a4 - a²b + 4ab² - 2a³b - 3b³
Edwin
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