【導(dǎo)讀】的單調(diào)減區(qū)間是;233恰有3個(gè)單調(diào)區(qū)間,則實(shí)數(shù)a的取值范圍是。axxxf,點(diǎn)),(yxP在該函數(shù)圖像上移動(dòng),過點(diǎn)P. 例3:已知函數(shù)??上的減函數(shù),則實(shí)數(shù)?xaaxxxf在區(qū)間),41(內(nèi)為減函數(shù),在區(qū)。求cb,的值;求)(xg的單調(diào)區(qū)間。,上是單調(diào)函數(shù),求a的范圍