Trang chủ » Hỏi đáp » Môn Toán A(x)=x^4-123x^3-123x^2-123x-125 tính a(122) 12/05/2023 A(x)=x^4-123x^3-123x^2-123x-125 tính a(122)
$\text{Đặt x=122}$ $\text{⇒$\left \{ {{123=x+1} \atop {125=x+3}} \right.$ }$ $\text{⇒A(122)=$x^{4}$ -123$x^{3}$ +123$x^{2}$ -123x +125}$ $\text{=$x^{4}$ -(x+1)$x^{3}$+(x+1)$x^{2}$ -(x+1)x+x+3}$ $\text{=$x^{4}$ -$x^{4}$ – $x^{3}$ + $x^{3}$ – $x^{2}$ + $x^{2}$ – x + x + 3 }$ $\text{=3}$ $\text{Vậy A(122)=3}$ Trả lời
