【導(dǎo)讀】1.會(huì)從幾何直觀探索并了解函數(shù)的單調(diào)性與其導(dǎo)數(shù)之間的關(guān)系,并會(huì)靈活應(yīng)用;3.通過(guò)對(duì)函數(shù)單調(diào)性的研究,加深對(duì)函數(shù)導(dǎo)數(shù)的理解,提高用導(dǎo)數(shù)解決實(shí)際問(wèn)題的能力.自變量的值21xx、,當(dāng)21xx?xf,則)(xf為該區(qū)間上的函數(shù),若在某區(qū)間上恒有0)(??若可導(dǎo)函數(shù))(xf在),(ba上單調(diào)遞增?xxxf在哪個(gè)區(qū)間上是增函數(shù),哪個(gè)區(qū)間上是減函數(shù).變式:討論函數(shù)xxysin2??