Question

can someone help me please :o

What are the possible number of positive, negative, and complex zeros of f(x) = -x6 - x5- x4 - 4x3 - 12x2 + 12 ?

answers

Positive: 4, 2, or 0; Negative: 2 or 0; Complex: 6, 4, 2, or 0
Positive: 3 or 1; Negative: 3 or 1; Complex: 4, 2, or 0
Positive: 3 or 1; Negative: 2 or 0; Complex: 4, 2, or 0
Positive: 1; Negative: 5, 3, or 1; Complex: 4, 2, or 0

Answer 1

Option 1
considering only DEcartes rule of signs

Answer 2

are these real zeroes? descartes does not work for complex zeroes