Question

x⁴-5x²-36=0 bhaskara​

Answer 1

$x^4-5x^2-36=0\\\\u=x^2\mathrm{\:e\:}u^2=x^4\\\\u^2-5u-36=0\\\\u=9,\:u=-4\\\\u=x^2,\:\mathrm{solucione\:para}\:x\\\\\mathrm{As\:solucoes\:finais\:sao}\\\\x=3,\:x=-3,\:x=2i,\:x=-2i$