SOLUTION: Locate the zeroes of each polynomial function. a. (x)= x³-4x²-9x+3 b. (x)= 2x³-x-4 c. (x)= x³-7x²+5x+1 d. (x)= x⁴-8x³+54x+105

Algebra ->  Test -> SOLUTION: Locate the zeroes of each polynomial function. a. (x)= x³-4x²-9x+3 b. (x)= 2x³-x-4 c. (x)= x³-7x²+5x+1 d. (x)= x⁴-8x³+54x+105      Log On


   



Question 1188667: Locate the zeroes of each polynomial function.
a. (x)= x³-4x²-9x+3
b. (x)= 2x³-x-4
c. (x)= x³-7x²+5x+1
d. (x)= x⁴-8x³+54x+105

Found 2 solutions by greenestamps, ikleyn:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


Use a graphing calculator. You can do that as easily as we can.

I looked at each of these using a graphing calculator, and most of the roots are irrational, so they are difficult or impossible to find algebraically. So by far the simplest way to find the APPROXIMATE DECIMAL roots is with a graphing calculator.

If you are supposed to use some different method, such as Newton's method, then re-post the problem stating what method is to be used.


Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.

(a) The roots of the polynomial  x^3 - 4x^2 - 9x + 3  are


        x%5B1%5D = 0.29703...
 
        x%5B2%5D = −1.82654...

        x%5B3%5D = 5.52951...


Explanation:


This polynomial has no rational roots that can be found using Rational Root Test.

Roots were found using cubic formulas.