Algebra
# Polynomial Factoring

Determine the number of sign changes in

$M(x) = x^6 + x^5 + x - 2.$

$T(x) = x^4 + x^3 - x^2 - 1$

By determining the types sign changes in $T(x)$ and $T(-x)$, determine the number of non-real complex roots of $T(x)$.

Is there any negative root to the polynomial

$U(x) = x^7 + x- 7 ?$