展开 e^t(t^2-2t-1)

解答

展开

e^{t} (t^{2} - 2 t - 1)

e^{t} t^{2} - 2 e^{t} t - e^{t}

求解步骤

e^{t} (t^{2} - 2 t - 1)

打开括号

= e^{t} t^{2} + e^{t} (- 2 t) + e^{t} (- 1)

使用加减运算法则

+ (- a) = - a

= e^{t} t^{2} - 2 e^{t} t - 1 \cdot e^{t}

乘以:

1 \cdot e^{t} = e^{t}

= e^{t} t^{2} - 2 e^{t} t - e^{t}

e x p an d e^{- \frac{2 x}{y}} - y^{3} \cdot (x^{2} - x y - y^{2})

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

e x p an d \frac{( 3 x ^{2} - 3 s + 9 )}{( x ( x ^{2} + 9 ) )}

e x p an d lo g_{2} (8) x^{2} y

e x p an d \frac{[ S r ( 1 + r ) ^{n} ]}{12 ( ( 1 + r ) ^{n} - 1 )}