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Find k if 2 is a root of x^3-(k+1)x+k=0

 Oct 18, 2017
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Find k if 2 is a root of x^3-(k+1)x+k=0

 

If 2 is a root, we have

 

(2)^3 - (k + 1)(2) + k  = 0      simplify

 

8 - 2k - 2 + k  = 0

 

6 - k  =  0         add k to both sides

 

6  =  k

 

 

cool cool cool

 Oct 18, 2017

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