Question

5xpower4 -22xpower2+8=0​

Answer 1

Answer:

$5x^4-22x^2+8=0\quad :\quad x=2,\:x=-2,\:x=\sqrt{\frac{2}{5}},\:x=-\sqrt{\frac{2}{5}}$

Step-by-step explanation:

$5x^4-22x^2+8=0$

$\mathrm{Rewrite\:the\:equation\:with\:}u=x^2\mathrm{\:and\:}u^2=x^4$

$5u^2-22u+8=0$

$u=4,\:u=\frac{2}{5}$

$\mathrm{Substitute\:back}\:u=x^2,\:\mathrm{solve\:for}\:x$

$\mathrm{The\:solutions\:are}$

$x=2,\:x=-2,\:x=\sqrt{\frac{2}{5}},\:x=-\sqrt{\frac{2}{5}}$