展开 22^k+5^{k+1}5

解答

展开

2 \cdot 2^{k} + 5^{k + 1} \cdot 5

2^{1 + k} + 5^{k + 2}

求解步骤

2 \cdot 2^{k} + 5^{k + 1} \cdot 5

2 \cdot 2^{k} = 2^{1 + k}

5^{k + 1} \cdot 5 = 5^{k + 2}

= 2^{k + 1} + 5^{k + 2}

e x p an d \frac{e ^{- 6 s} + 6 s}{s ( s ^{2} + 9 s + 18 )}

e x p an d l im x \Rightarrow 1 + x (1 - x) - 1

e x p an d \frac{x + 1}{( x - 3 ) ^{2}}

s im pl i f y (x + i y) e^{x + i y}

e x p an d 2 x^{2} \cdot ((1 + x^{2}) y^{'} (x) + 4 x y)