Question

函數(shù)的零點(diǎn)個(gè)數(shù)是    個(gè)．

Answer 1

【答案】分析：把函數(shù)每一段上的零點(diǎn)求出即可，本題函數(shù)的零點(diǎn)轉(zhuǎn)化為對(duì)應(yīng)方程的實(shí)數(shù)根即可．
解答：解：①當(dāng)x≤0時(shí)，可求出f（x）=0的實(shí)數(shù)根，即x²+2x-3=0，解得：x₁=-3，x₂=1（舍去）．
②當(dāng)x＞0時(shí)，可求出f（x）=0的實(shí)數(shù)根，即-2+lnx=0，解得：x=e²．
所以函數(shù)的零點(diǎn)個(gè)數(shù)是2．
故答案為：2．
點(diǎn)評(píng)：本題考查分段函數(shù)的零點(diǎn)，把函數(shù)的零點(diǎn)轉(zhuǎn)化為對(duì)應(yīng)方程的實(shí)數(shù)根是解本題的關(guān)鍵．