HOW TO FACTOR THIS? x^3 - 4x^2 + 3x -12?

Question

ANSWER IS (x-4)(x^2 + 3)

BUT HOW DO YOU GET THERE? (BTW, THE TEACHER'S ONLY TAUGHT FACTORING TRINOMIALS.)

Answer 1

to factor, you factor by grouping. First use parentheses to make groups of 2 terms each. This is what it looks like

(x^3-4x^2)+(3x-12) Now find the GCF in each set of parentheses and factor it out. You wind up with this

x^2(x-4)+3(x-4) Now we combine like terms, the like term being x-4. So we wind up with our answer being:

(x^2+3)(x-4)