If $f\left(x\right)=a_{100}{x}^{100}$ , 
$g\left(x\right)=a_{100}{x}^{100}+a_{99}{x}^{99}$  ,
  $h\left(x\right)=a_{49}{x}^{49}+a_{48}{x}^{48}+a_{47}{x}^{47}+\mathrm{.....}+a_2{x}^2+a_{1}x+a_0$, then 

$(a_0,a_1,a_2\mathrm{......}{a}_{100}$  or non zero real numbers)

If r consecutive powers of x are missing from a polynomial, then (1) it has atleast r  imaginary roots if r is even and (2) either $(r+1)or(r-1)$ imaginary roots if r is odd  depending on the sign of coefficients just next to the gap.