Question

4x4-18x2+8=0 помогите плз

Answer 1

$4 x^{4} -18 x^{2} +8=0 \ x^{2} =t \ 4t^{2} -18t+8=0 \ D=324-128=196 \ sqrt{D} =14 \ t _{1} = frac{18-14}{8} = frac{1}{2} \ t _{2} = frac{18+14}{8} =4 \ x^{2} = frac{1}{2} \ x _{1} = frac{1}{ sqrt{2} } = frac{ sqrt{2} }{2} \ x^{2} =4 \ x _{2} =2$