①當(dāng)x為第一象限角時(shí),y=
sinx |
sinx |
cosx |
cosx |
tanx |
tanx |
cotx |
cotx |
②當(dāng)x為第二象限角時(shí),y=
sinx |
sinx |
cosx |
cosx |
tanx |
tanx |
cotx |
cotx |
③當(dāng)x為第三象限角時(shí),y=-
sinx |
sinx |
cosx |
cosx |
tanx |
tanx |
cotx |
cotx |
④當(dāng)x為第一象限角時(shí),y=-
sinx |
sinx |
cosx |
cosx |
tanx |
tanx |
cotx |
cotx |
∴函數(shù)y=
sinx |
|sinx| |
|cosx| |
cosx |
tanx |
|tanx| |
|cotx| |
cotx |
故選B.