Find all zeros, real and nonreal, of the function f(x)=4x4+8x3+2x28x6\displaystyle {f{{\left({x}\right)}}}={4}{x}^{{4}}+{8}{x}^{{3}}+{2}{x}^{{2}}-{8}{x}-{6}. Give exact answers, using radicals and fractions, not decimals.

The zeros are