因数 x^2+4x^2-4x-16

解

因数

x^{2} + 4 x^{2} - 4 x - 16

5 (x - \frac{2 ( 1 + 21 )}{5}) (x + \frac{2 ( 21 - 1 )}{5})

解答ステップ

x^{2} + 4 x^{2} - 4 x - 16

類似した元を足す:

x^{2} + 4 x^{2} = 5 x^{2}

= 5 x^{2} - 4 x - 16

書き換え

= 5 (x^{2} - \frac{4 x}{5} - \frac{16}{5})

因数

x^{2} - \frac{4 x}{5} - \frac{16}{5} : (x - \frac{2 ( 1 + 21 )}{5}) (x - \frac{2 ( 1 - 21 )}{5})

5 (x - \frac{2 ( 1 + 21 )}{5}) (x - \frac{2 ( 1 - 21 )}{5})

因数

2 (1 - 21) : - 2 (21 - 1)

= 5 (x - \frac{2 ( 1 + 21 )}{5}) (x - \frac{- 2 ( 21 - 1 )}{5})

分数の規則を適用する:

\frac{- a}{b} = - \frac{a}{b}

= 5 (x - \frac{2 ( 1 + 21 )}{5}) (x - (- \frac{2 ( 21 - 1 )}{5}))

規則を適用

- (- a) = a

= 5 (x - \frac{2 ( 1 + 21 )}{5}) (x + \frac{2 ( 21 - 1 )}{5})