合并 (e^2)/(s-1)+4/(s^2)+a/s

解答

合并

\frac{e ^{2}}{s - 1} + \frac{4}{s ^{2}} + \frac{a}{s}

\frac{e ^{2} s ^{2} + 4 ( s - 1 ) + a s ( s - 1 )}{s ^{2} ( s - 1 )}

求解步骤

\frac{e ^{2}}{s - 1} + \frac{4}{s ^{2}} + \frac{a}{s}

s - 1, s^{2}, s

的最小公倍数:

s^{2} (s - 1)

根据最小公倍数调整分式

= \frac{e ^{2} s ^{2}}{( s - 1 ) s ^{2}} + \frac{4 ( s - 1 )}{s ^{2} ( s - 1 )} + \frac{a s ( s - 1 )}{s ^{2} ( s - 1 )}

因为分母相等，所以合并分式:

\frac{a}{c} \pm \frac{b}{c} = \frac{a \pm b}{c}

= \frac{e ^{2} s ^{2} + 4 ( s - 1 ) + a s ( s - 1 )}{s ^{2} ( s - 1 )}

s im pl i f y 2 213 5^{\circ}

s im pl i f y sec (x) cot (x)

s im pl i f y (a - b) - (b - a)^{2}

s im pl i f y (\frac{1}{3})^{3} \cdot (\frac{3}{10})^{3} \cdot (\frac{5}{7})^{3}

s im pl i f y (5 - 3 i) (- 2 + 4 i)