展开 2(x+Δx)^3-6(x+Δx)^2-7(x+Δx)+11

解答

展开

2 (x + Δ x)^{3} - 6 (x + Δ x)^{2} - 7 (x + Δ x) + 11

2 x^{3} + 6Δ x^{3} + 6 Δ^{2} x^{3} + 2 Δ^{3} x^{3} - 6 x^{2} - 12Δ x^{2} - 6 Δ^{2} x^{2} - 7 x - 7Δ x + 11

求解步骤

2 (x + Δ x)^{3} - 6 (x + Δ x)^{2} - 7 (x + Δ x) + 11

乘开

- 7 (x + Δ x) : - 7 x - 7Δ x

= 2 (x + Δ x)^{3} - 6 (x + Δ x)^{2} - 7 x - 7Δ x + 11

化简

2 (x + Δ x)^{3} - 6 (x + Δ x)^{2} - 7 x - 7Δ x + 11 : 2 x^{3} + 6Δ x^{3} + 6 Δ^{2} x^{3} + 2 Δ^{3} x^{3} - 6 x^{2} - 12Δ x^{2} - 6 Δ^{2} x^{2} - 7 x - 7Δ x + 11

= 2 x^{3} + 6Δ x^{3} + 6 Δ^{2} x^{3} + 2 Δ^{3} x^{3} - 6 x^{2} - 12Δ x^{2} - 6 Δ^{2} x^{2} - 7 x - 7Δ x + 11

e x p an d (l - ∣ x ∣) cos (\frac{nπ x}{l})

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

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

e x p an d \frac{x ^{2}}{( 1 + 0.6 x ) ( 1 - x )}

e x p an d \frac{( 1 + 2 x ) ^{4}}{8}