SOLUTION: What are the real zeros of the function {{{x^3+6x^2-13x-42}}}
I know you have to find the common factors but im not sure what to do after?
please show your steps on how you solve
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-> SOLUTION: What are the real zeros of the function {{{x^3+6x^2-13x-42}}}
I know you have to find the common factors but im not sure what to do after?
please show your steps on how you solve
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Question 966865: What are the real zeros of the function
I know you have to find the common factors but im not sure what to do after?
please show your steps on how you solved this thank you! Answer by ikleyn(52794) (Show Source):
Look for the roots of the polynomial among the divisors of the constant term .
The divisors are . . . , +/-2, +/-3, +/- 6, +/-7, . . .
I was lucky and quickly found that is the root.
(To be honest, I used an Excel spreadsheet for it :) ).
Knowing it, you can divide your original polynomial by the binomial .
Do you know how to divide a polynomial by a binomial?
Use the same scheme as you use for dividing integer numbers (long division).
After completing this, you will get
= ..
Then you can find the roots of the quadratic polynomial using the quadratic formula. In this way I found that the roots are -7 and -2.
