利用定積分定義計(jì)算下列積分:
已知函數(shù)f(x,y)在點(diǎn)(0,0)的某個(gè)鄰域內(nèi)連續(xù),且,則下述四個(gè)選項(xiàng)中正確的是()
A.點(diǎn)(0,0)不是f(x,y)的極值點(diǎn). B.點(diǎn)(0,0)是f(x,y)的極大值點(diǎn), C.點(diǎn)(0,0)是f(x,y)的極小值點(diǎn), D.根據(jù)所給條件無法判斷(0,0)是否為f(x,y)的極值點(diǎn)