Question

Помогите с заданием 2x^4-5x^2-12=0

Answer 1

$2 x^{4}-5 x^{2} -12=0 \\ x^{2} =t \\ 2t^{2}-5t-12=0 \\ D=25+96=121=11^{2} \\ t_{1,2} = \frac{5+-11}{4} \\ t_{1}=4.......t_{2}=-1,5 \\ x^{2}=4;.......x=+-2 \\ x^{2} =-1,5;........x \neq$

Ответ: +-2