SOLUTION: I need help with this problem. I'm having great difficulty with it. 2x^7-16x^6+6x^5

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I need help with this problem. I'm having great difficulty with it. 2x^7-16x^6+6x^5      Log On


   

Question 155040This question is from textbook Introductory and Intermediate Algebra through applications
: I need help with this problem. I'm having great difficulty with it.
2x^7-16x^6+6x^5 This question is from textbook Introductory and Intermediate Algebra through applications

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
I assume you mean,
2x%5E7-16x%5E6%2B6x%5E5=0
and you want to find the solutions (zeros).
2x%5E7-16x%5E6%2B6x%5E5=0
x%5E5%282x%5E2-16x%2B6%29=0
Look at each term for solution.
First term.
x%5E5=0
x%5B1%5D=x%5B2%5D=x%5B3%5D=x%5B4%5D=x%5B5%5D=0
Five zeros at x=0.
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.
.
Second term
2x%5E2-16x%2B6=0
Use the quadratic formula,
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-%28-16%29+%2B-+sqrt%28+%28-16%29%5E2-4%2A2%2A6+%29%29%2F%282%2A2%29+
x+=+%2816+%2B-+sqrt%28+256-48+%29%29%2F%284%29+
x+=+%2816+%2B-+sqrt%28+208+%29%29%2F%284%29+
x+=+%2816+%2B-+sqrt%28+16%2A13+%29%29%2F%284%29+
x+=+%2816+%2B-+4sqrt%28+13+%29%29%2F%284%29+
x%5B6%2C7%5D+=+4+%2B-+sqrt%28+13+%29+
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.
.
+graph%28+300%2C+300%2C+-2%2C+10%2C+-0.2%2C+0.2%2C+2x%5E7-16x%5E6%2B6x%5E5%29+
A little difficult to see but here's the graphical verification.