SOLUTION: Factor {{{x^3+5x+3x^2+15}}}

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Question 49055: Factor x%5E3%2B5x%2B3x%5E2%2B15
Answer by AnlytcPhil(1806) About Me  (Show Source):
You can put this solution on YOUR website!
Factor

x³ + 5x + 3x² + 15

Factor the first two terms only by
taking out x

x(x² + 5) + 3x² + 15

Factor the last two terms only by
taking out 3

x(x² + 5) + 3(x² + 5)

Now you see that the term
x(x² + 5) and the term
3(x² + 5) have the common
factor (x² + 5)

x(x² + 5) + 3(x² + 5)

So factor out the red factor (x² + 5)
on the left and leave the black factors 
in parentheses on the right:

(x² + 5)(x + 3)

Edwin