Question 43582
{{{g(x) = 9x^3 - 7x^2 + 10x - 4}}}
Look at the value coefficients: +9 then -7 then +10 then -4
The sign changes three times, so you have a chance of three positive real roots.
{{{g(-x) = 9(-x)^3 - 7(-x)^2 + 10(-x) - 4}}}
{{{g(-x) = -9x - 7x - 10x - 4}}}
Look at the value coefficients: -9 then -7 then -10 then -4
The sign never changes, so you obviously know that there are absolutely no negative real roots.
Pos: .. 3 .. 1
Neg: . 0 .. 0
Imag: 0 .. 2
You can take two away from the positives and add to the imaginery.