应用证明
   (1)
   (2)

A.174.24.96:6088/Latex/latex.action?latex=XGludF97MH1eeytcaW5mdHkgfWVeey1hdF4yfWR0PVxmcmFje1xzcXJ0e1xwaX19ezJ9YV57LVxm%0D%0AcmFjezF9ezJ9fVxsZWZ0KCBh77yeMCBccmlnaHQpLA%3D%3D'
B.174.24.96:6088/Latex/latex.action?latex=XGludF97MH1eeytcaW5mdHkgfXReMmVeey1hdF4yfWR0PVxmcmFje1xzcXJ0e1xwaX19ezR9YV57%0D%0ALVxmcmFjezN9ezJ9fTs%3D'
C.174.24.96:6088/Latex/latex.action?latex=XGludF97MH1eeytcaW5mdHkgfXReezJufWVeey1hdF4yfWR0PVxmcmFje1xzcXJ0e1xwaX19ezJ9%0D%0AXGZyYWN7MVxjZG90IDNcY2RvdFxjZG90cyBcY2RvdFxsZWZ0KCAybi0xIFxyaWdodCl9ezJebn1h%0D%0AXnstXGxlZnQoIG4rXGZyYWN7MX17Mn0gXHJpZ2h0KX0u'

【参考答案】

(1)利用积分公式，有


(2)

(递推公式)，
由于，所以