结束上页 下页证 xeeeex xxxx ch )(21)(21)sh (
证例 16 证明双曲函数的导数公式?
xeeeex xxxx sh )(21)(21)ch (
证 xeeex xxxx c h )(21)(21)s h ( 证 xeex xxx c h ))(21)s h ( 证 xeeeex xxxx h )(21)(21)sh (
xeeeex xxxx s h )(21)(21)c h ( xeeex xxx s h )(21)c h ( xeeeex xxxx h )(21)(21ch (
( s h x ) c h x? ( c h x ) s h x? xx 2ch 1)( t h
提示?
(e?x)e?x(?x)e?x?
x
xx
x
xxxx
x
xx
2
22
2 ch
shch
ch
)ch(shch)sh()
ch
sh()( th
x2ch
1
x
xx
x
xxxx
x
xx
2
22
2 ch
shch
ch
)ch(shchsh()
ch
sh()( t h
x2ch
1
x
xx
x
xxxx
x
xx
2
22
2 ch
shch
ch
)ch(shch)sh()
ch
sh)( th
x2ch
1
x
xx
x
xxxx
x
xx
2
22
2 ch
shch
ch
)ch(shch)()
ch
sh()(th
x2ch
1
结束