21x^3+67x^2-36=0 solutins
tried: ±1, ±2, ±3
success at x = -3
by synthetic division
21x^3+67x^2-36=(x+3)(21x^2+ 4x - 12)
= (x+3)(3x-2)(7x+6)
so what do you think?
success at x = -3
by synthetic division
21x^3+67x^2-36=(x+3)(21x^2+ 4x - 12)
= (x+3)(3x-2)(7x+6)
so what do you think?