Welcome to Westonci.ca, your one-stop destination for finding answers to all your questions. Join our expert community now! Experience the convenience of finding accurate answers to your questions from knowledgeable professionals on our platform. Get detailed and accurate answers to your questions from a dedicated community of experts on our Q&A platform.

f (x) = x5 − 8x4 + 21x3 − 12x2 − 22x + 20

Three roots of this polynomial function are −1, 1, and 3 + i.

Which of the following describes the number and nature of all the roots of this function?


f (x) has two real roots and one imaginary root.

f (x) has three real roots.

f (x) has five real roots.

f (x) has three real roots and two imaginary roots.


Sagot :

Answer:

  f(x) has three real roots and two imaginary roots.

Step-by-step explanation:

The function is degree 5, so will have 5 roots in total. 2 real roots and one complex root are shown. Complex roots come in pairs, so there will be one more, but cannot be two more.

  f(x) has three real roots and two imaginary roots.

__

All five roots must be accounted for. This leaves out the first two choices. The given complex root eliminates the third choice.

Answer:

D

Step-by-step explanation:

did the test