展开 ((x-3)(x+4))/((x+3)(-x^3+9x^2-25x+35))

解答

展开

\frac{( x - 3 ) ( x + 4 )}{( x + 3 ) ( - x ^{3} + 9 x ^{2} - 25 x + 35 )}

\frac{x ^{2} + x - 12}{- x ^{4} + 6 x ^{3} + 2 x ^{2} - 40 x + 105}

求解步骤

\frac{( x - 3 ) ( x + 4 )}{( x + 3 ) ( - x ^{3} + 9 x ^{2} - 25 x + 35 )}

乘开

(x + 3) (- x^{3} + 9 x^{2} - 25 x + 35) : - x^{4} + 6 x^{3} + 2 x^{2} - 40 x + 105

= \frac{( x - 3 ) ( x + 4 )}{- x ^{4} + 6 x ^{3} + 2 x ^{2} - 40 x + 105}

乘开

(x - 3) (x + 4) : x^{2} + x - 12

= \frac{x ^{2} + x - 12}{- x ^{4} + 6 x ^{3} + 2 x ^{2} - 40 x + 105}

e x p an d (2 x^{3} + 4 x^{2} - 5 x) l e f t (3 x y - 4 y)

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

e x p an d (cos (2 π t) - 2 π t \cdot sin (2 π t))^{2}

e x p an d \frac{d}{d v} ((p (v)) (p (v) + \frac{5.9}{v ^{2}})) + (v - 1.7)

e x p an d v (2, - 1) f (1, - 1)