(1)化簡(jiǎn)下列各式:
①-(-6);
②-(+6);
③-[-(+6)];
④-{-[-(+6)]};
(2)想一想:當(dāng)+6前面有2011個(gè)正號(hào)時(shí),化簡(jiǎn)結(jié)果為_(kāi)_____;當(dāng)+6前面有2011個(gè)負(fù)號(hào)時(shí),化簡(jiǎn)結(jié)果為_(kāi)_____;當(dāng)+6前面有2012個(gè)負(fù)號(hào)時(shí),化簡(jiǎn)結(jié)果為_(kāi)_____.
解:(1)①-(-6)=6;
②-(+6)=-6;
③-[-(+6)]=6;
④-{-[-(+6)]}=-6;
(2)當(dāng)+6前面有2011個(gè)正號(hào)時(shí),化簡(jiǎn)結(jié)果為+6;
當(dāng)+6前面有2011個(gè)負(fù)號(hào)時(shí),化簡(jiǎn)結(jié)果為-6;
當(dāng)+6前面有2012個(gè)負(fù)號(hào)時(shí),化簡(jiǎn)結(jié)果為+6.
故答案為:+6,-6,+6.
分析:(1)根據(jù)相反數(shù)的定義分別進(jìn)行化簡(jiǎn)即可;
(2)根據(jù)(1)的計(jì)算結(jié)果猜想即可得解.
點(diǎn)評(píng):本題考查了利用相反數(shù)的定義化簡(jiǎn),熟記概念并仔細(xì)觀察化簡(jiǎn)結(jié)果與負(fù)號(hào)的關(guān)系是解題的關(guān)鍵.