閱讀下列材料,解答后面的問(wèn)題:
在二次根式的學(xué)習(xí)中,我們不僅要關(guān)注二次根式本身的性質(zhì)、運(yùn)算,還要用到與分式、不等式相結(jié)合的一些運(yùn)算.如:
①要使二次根式a-2有意義,則需a-2≥0,解得:a≥2;
②化簡(jiǎn):1+1n2+1(n+1)2,則需計(jì)算1+1n2+1(n+1)2,而1+1n2+1(n+1)2=n2(n+1)2+(n+1)2+n2n2(n+1)2=n2(n+1)2+n2+2n+1+n2n2(n+1)2=n2(n+1)2+2n2+2n+1n2(n+1)2=n2(n+1)2+2n(n+1)+1n2(n+1)2=[n(n+1)+1]2n2(n+1)2所以1+1n2+1(n+1)2=[n(n+1)+1]2n2(n+1)2=n(n+1)+1n(n+1)=1+1n(n+1)=1+1n-1n+1.
(1)根據(jù)二次根式的性質(zhì),要使a+23-a=a+23-a成立,求a的取值范圍;
(2)利用①中的提示,請(qǐng)解答:如果b=a-2+2-a+1,求a+b的值;
(3)利用②中的結(jié)論,計(jì)算:1+112+122+1+122+132+1+132+142+?+1+120222+120232.
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【答案】見(jiàn)試題解答內(nèi)容
【解答】
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發(fā)布:2024/7/5 8:0:9組卷:140引用:1難度:0.6