(1)22-2×+|-2|+2012
(2)先化簡(jiǎn),后求值:(x+3)2+(x+2)(x-2),其中x=-2.
【答案】分析:(1)原式利用負(fù)數(shù)的絕對(duì)值等于它的相反數(shù)及零指數(shù)冪法則計(jì)算,即可得到結(jié)果;
(2)原式第一項(xiàng)利用完全平方公式展開,第二項(xiàng)利用平方差公式化簡(jiǎn),去括號(hào)合并得到最簡(jiǎn)結(jié)果,將x的值代入計(jì)算即可求出值.
解答:解:(1)原式=4-1+2+1=6;
(2)原式=x2+6x+9+x2-4=2x2+6x+5,
當(dāng)x=-2時(shí),原式=8-12+5=1.
點(diǎn)評(píng):此題考查了整式的混合運(yùn)算-化簡(jiǎn)求值,以及實(shí)數(shù)的運(yùn)算,涉及的知識(shí)有:平方差公式,完全平方公式,多項(xiàng)式乘多項(xiàng)式,去括號(hào)法則,以及合并同類項(xiàng)法則,熟練掌握公式及法則是解本題的關(guān)鍵.
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