Could I get help on one more?
What are the zeros of the polynomial function?
f(x)=x4+2x3−16x2−2x+15
Options
−5
−1
0
1
3
5
Please and thank you! 0^>
\(x^4+2x^3 -16x^2 -2x+15 =\\ (x^4-16x^2+15) + (2x^3-2x)= \\ (x^2-15)(x^2-1) + 2x(x^2-1) = \\ (x^2+2x-15)(x^2-1) = \\ (x+5)(x-3)(x-1)(x+1) \\ \\ \text{zeros are read off as }\\ x=-5,~3,~1,~-1\)
+360 
