展开 (e^u+e^{-u})(e^u-e^{-u})

解答

展开

(e^{u} + e^{- u}) (e^{u} - e^{- u})

e^{2 u} - e^{- 2 u}

求解步骤

(e^{u} + e^{- u}) (e^{u} - e^{- u})

使用平方差公式:

(a + b) (a - b) = a^{2} - b^{2}

a = e^{u}, b = e^{- u}

= (e^{u})^{2} - (e^{- u})^{2}

化简

(e^{u})^{2} - (e^{- u})^{2} : e^{2 u} - e^{- 2 u}

= e^{2 u} - e^{- 2 u}

e x p an d, x (x 2 + y^{2})

e x p an d (3 + 1)^{7}

e x p an d \frac{4 x + 5}{( x + 5 ) ( 5 x - 1 )}

\frac{d}{d t} ((k) (s k^{a} - nk))

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