Question 364534
Use synthetic division to verify the upper bound and lower bound of the zeros of f. 
f(x) = 2x^4 -8x +3 
Upper bound: x= 3; Lower bound: x= -4 
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3)....2....0....0....-8....3
.......2.....6...18....46....|..141
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So f(3) = 141
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-4)....2....0....0....-8....3
........2....-8....32....-136....|..547
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So f(-4) = 547
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Cheers,
Stan H.