Question

решить уравнение 2x³-8x²+9x-36=0

Answer 1

$2 x^{3} -8 x^{2} +9x-36=0\\ 2 x^{2} (x-4)+9(x-4)=0\\(2 x^{2} +9)(x-4)=0\\ 2 x^{2} +9=0\\ 2 x^{2} =-9 \\ x^{2} =-4.5 \\ x^{2} \neq -4.5 \\ \\ x-4=0\\x=4$