展开 ((x+2)^2*(x-1)(x+1))/(2x^2-7x-4)

解答

展开

\frac{( x + 2 ) ^{2} \cdot ( x - 1 ) ( x + 1 )}{2 x ^{2} - 7 x - 4}

\frac{x ^{4} + 3 x ^{2} + 4 x ^{3} - 4 x - 4}{2 x ^{2} - 7 x - 4}

求解步骤

\frac{( x + 2 ) ^{2} ( x - 1 ) ( x + 1 )}{2 x ^{2} - 7 x - 4}

(x + 2)^{2} = x^{2} + 4 x + 4

= \frac{( x ^{2} + 4 x + 4 ) ( x - 1 ) ( x + 1 )}{2 x ^{2} - 7 x - 4}

乘开

(x^{2} + 4 x + 4) (x - 1) (x + 1) : x^{4} + 3 x^{2} + 4 x^{3} - 4 x - 4

= \frac{x ^{4} + 3 x ^{2} + 4 x ^{3} - 4 x - 4}{2 x ^{2} - 7 x - 4}

e x p an d (1 - e^{t} + 3 e^{- 4 t}) \cdot cos (3 t)

e x p an d \frac{500 0 _{0}}{( 1 + 5 ) ^{0}}

e x p an d 3 x (2 x + 2)

e x p an d \frac{( 10 + 2 x ) \frac{d}{d t} ( ( x ) 10 )}{7 + x}

e x p an d - 9 (2) - 1