展开 (x^2+2x+5=0)(x^2-x-6)

解答

展开

(x^{2} + 2 x + 5 = 0) (x^{2} - x - 6)

x^{4} + x^{3} - 8 x^{2} - 12 x + 5 = 0

求解步骤

(x^{2} + 2 x + 5 = 0) (x^{2} - x - 6)

= (x^{2} + 2 x + 5 \cdot 0 =) (x^{2} - x - 6)

打开括号

x^{2} x^{2} + x^{2} (- x) + x^{2} (- 6) + 2 x x^{2} + 2 x (- x) + 2 x (- 6) + 5 = 0 \cdot x^{2} + 5 = 0 \cdot (- x) + 5 = 0 \cdot (- 6)

使用加减运算法则

+ (- a) = - a

x^{2} x^{2} - x^{2} x - 6 x^{2} + 2 x^{2} x - 2 xx - 2 \cdot 6 x + 5 = 0 \cdot x^{2} - 5 = 0 \cdot x - 5 = 0 \cdot 6

化简

x^{2} x^{2} - x^{2} x - 6 x^{2} + 2 x^{2} x - 2 xx - 2 \cdot 6 x + 5 = 0 \cdot x^{2} - 5 = 0 \cdot x - 5 = 0 \cdot 6 : x^{4} + x^{3} - 8 x^{2} - 12 x + 5 = 0

x^{4} + x^{3} - 8 x^{2} - 12 x + 5 = 0

e x p an d \frac{x + 3 ( x ^{2} - 1 )}{2}

e x p an d (- 2, 7) (11, - π)

e x p an d (- x y^{'} (x) - y) x y

e x p an d \frac{( 4 - x ^{2} ) ( x 3 )}{4}

e x p an d 8 (x + 43 = 56)