展开 U(t-4)(2-t^2)+2e^{-pit}+sin(3t)-t^3

解答

展开

U (t - 4) (2 - t^{2}) + 2 e^{- π t} + sin (3 t) - t^{3}

- U t^{3} + 4 U t^{2} + 2 U t - 8 U + 2 e^{- π t} + sin (3 t) - t^{3}

求解步骤

U (t - 4) (2 - t^{2}) + 2 e^{- π t} + sin (3 t) - t^{3}

乘开

U (t - 4) (2 - t^{2}) : - U t^{3} + 4 U t^{2} + 2 U t - 8 U

= - U t^{3} + 4 U t^{2} + 2 U t - 8 U + 2 e^{- π t} + sin (3 t) - t^{3}

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

e x p an d (4 x^{3} y^{2} - 6 x^{2} y - 2 x - 3) d x + (2 x^{4} y - 2 x^{3}) d y

e x p an d (k + 1)! (k + 2)

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

s im pl i f y 16 π (0.02 \cdot \frac{0.0 1 ^{2}}{2} - \frac{0.0 1 ^{3}}{3})