因数 5x^2+16x+12.8

解

因数

5 x^{2} + 16 x + 12.8

(2.23606 \dots x + 3.57770 \dots)^{2}

解答ステップ

5 x^{2} + 16 x + 12.8

5 x^{2} + 16 x + 12.8

を書き換え

(5 x)^{2} + 2 \cdot 2.23606 \dots x \cdot 3.57770 \dots + (12.8)^{2}

= (5 x)^{2} + 2 \cdot 2.23606 \dots x \cdot 3.57770 \dots + (12.8)^{2}

完全平方式を適用する:

(a + b)^{2} = a^{2} + 2 ab + b^{2}

a = 2.23606 \dots x, b = 3.57770 \dots

= (2.23606 \dots x + 3.57770 \dots)^{2}