展开 2(5x^2+3x-6)^2

解答

展开

2 (5 x^{2} + 3 x - 6)^{2}

50 x^{4} + 60 x^{3} - 102 x^{2} - 72 x + 72

求解步骤

2 (5 x^{2} + 3 x - 6)^{2}

(5 x^{2} + 3 x - 6)^{2} = 25 x^{4} + 30 x^{3} - 51 x^{2} - 36 x + 36

= 2 (25 x^{4} + 30 x^{3} - 51 x^{2} - 36 x + 36)

打开括号

= 2 \cdot 25 x^{4} + 2 \cdot 30 x^{3} + 2 (- 51 x^{2}) + 2 (- 36 x) + 2 \cdot 36

使用加减运算法则

+ (- a) = - a

= 2 \cdot 25 x^{4} + 2 \cdot 30 x^{3} - 2 \cdot 51 x^{2} - 2 \cdot 36 x + 2 \cdot 36

化简

2 \cdot 25 x^{4} + 2 \cdot 30 x^{3} - 2 \cdot 51 x^{2} - 2 \cdot 36 x + 2 \cdot 36 : 50 x^{4} + 60 x^{3} - 102 x^{2} - 72 x + 72

= 50 x^{4} + 60 x^{3} - 102 x^{2} - 72 x + 72

e x p an d r (r + 2 cos (θ) = 0)

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

e x p an d (e u + e + 1)^{2}

e x p an d \frac{x + 9}{x ( x + 1 ) ^{2}}

e x p an d (A x + B) e^{4 x}