first notice that you can factor out the y, leaving
y(y^2-13y+36)
Now you want two numbers that add to -13 and multiply to 36. Obviously they must both be negative. Easy factors of 36 are
1,36 2,18 3,12 4,9
It's clear that we want 4 and 9, so our polynomial is
y(y-4)(y-9)
This factoring by inspection is mainly a skill acquired by doing a lot of problems, so you get to recognize likely factors.
y^3-13y^2+36y
Can someone please show me step by step that way I can understand. Thank you
2 answers
Thank you soo much.. I have a lot of trouble with factoring
1 answer