Question

f(x)=x^3+2x^2+4x+8
find all the zeros

Answer 1

Do you know how to factor by grouping?

Answer 2

f(x) is zero when x=-2

Answer 3

but how u find it ?

Answer 4

u put -2 in place of x in the expression and then calculate

Answer 5

from any other numbgers

Answer 6

Or you can factor the expression by grouping to find the zeros instead of doing the guess zero thing.

Answer 7

yap in that way also u can do it ,actually f(x) will be zero when x=-4 and -2
but if you are asked to do it by factor theorem ,then u gottta follow that guess zero method.