Question 217753
12a^3 -9a^2 +4a -3
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3a^2(4a -3) +1(4a-3)
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,,,,,,hard  to  visualize  but  if  b=(4a-3),,,,this  becomes 3a^2b +1b,,,,,or b(3a^2 +1),,,,which  becomes  by  subst  back,,,,(4a-3)(3a^2 +1)
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(4a-3)(3a^2 +1),,,,answer
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check,,,,FOIL,,,,12a^3 +4a -9a^2 -3,,,,,ok
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2p^3 +5p^2 +6p +15
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p^2(2p +5),,,,,+ 3(2p+5)
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(p^2 +3) (2p+5),,,,,,answer
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check,,,,FOIL,,,,,2p^3 +5p^2 +6p +15,,,,,ok
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after  factoring by grouping,,,,,check  to  see  if  either  of  the  factors  can  be  factored  further,,,,,in  our  problems,,,,no
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