State how many imaginary and real zeros the function has.

f(x) = x^3 - 20x^2 + 123x - 216

Question

State how many imaginary and real zeros the function has.

f(x) = x^3 - 20x^2 + 123x - 216

anonymous · Answer

how many real and how many imaginer and how do u find them

asnaseer · Answer

have you learnt about Descartes Rule of Signs?

anonymous · Answer

no not yet

dumbcow · Answer

well easy way is graph it ...but i think you are talking about Descartes rule of signs
count the sign changes

ooh nevermind

asnaseer · Answer

do you know what method you are expected to use here?

anonymous · Answer

my online textbook won't open so I'm not sure

dumbcow · Answer

use your graphing calculator and see how many times it crosses x-axis

asnaseer · Answer

what about dumbcow's suggestion of just graphing it?

anonymous · Answer

ok 1 sec

anonymous · Answer

2 img & 1 real

asnaseer · Answer

dumbcow · Answer

remember imaginary roots always come in pairs

anonymous · Answer

so theres not to imaginary

dumbcow · Answer

anonymous · Answer

ohhhhhhhhh !!!! now i get it

asnaseer · Answer

good :) - thx to dumbcow.