七年級(jí)數(shù)學(xué)講義

專業(yè)好文檔1、 下列運(yùn)算：；，其中不正確的有 。2、 已知：的值為 。3、 已知的值為 。4、 = 。5、 若= 。6、 = 。7、 一個(gè)棱長(zhǎng)為的正方體，在某種物質(zhì)的作用下，棱長(zhǎng)以每天擴(kuò)大到原來(lái)的倍的速度膨脹，則10天后該正方體的體積為 。8、 的個(gè)位數(shù)字是 。冪的大小比較方法：（1）直接計(jì)算法 已知a，b,c分別為，則a,b,c按從小到大的順序排列的結(jié)果是 。（2） 差值比較法 利用比較的大小。（3） 商值比較法 已知，那么P，Q的大小關(guān)系是？（4） 底數(shù)比較法 數(shù)的大小關(guān)系是？（5） 指數(shù)比較法 若，則a，b，c的大小關(guān)系是？（6） 乘方比較法 已知：，比較a和b的大小。（7） 倒數(shù)比較法 比較的大小。(8) 中間數(shù)比較法 比較的大小。1、 若= 。2、 已知= 。3、 計(jì)算：（n為正整數(shù)）4、 解關(guān)于x的方程：1、 計(jì)算的結(jié)果為 。2、 化簡(jiǎn)的結(jié)果是 。3、 若，則適合條件的m，k的值分別等于？4、 若的值是？5、 先化簡(jiǎn)，后求值。 ，其中x=1,y=2.6、 我們規(guī)定下列運(yùn)算： 7、 先化簡(jiǎn)，再求值：（1） 其中x=5 y=1（2） 其中 （3） 其中 x=28.已知 求 的值。9.已知 求 的值。10.解方程：11.若多項(xiàng)式與的積不含x三次方的項(xiàng)，求a和b的值。12.如圖，正方形卡片A類，B類和長(zhǎng)方形卡片C類若干張，如果要拼一個(gè)長(zhǎng)為（a+2b），寬為（a+b）的大長(zhǎng)方形，則需要C類卡片 張。（1） 根據(jù)前面各式的規(guī)律可得： （n為正整數(shù)）（2） 利用上述規(guī)律求的值。Winger Tuivasa-Sheck, who scored two tries in the Kiwis 20-18 semi-final win over England, has been passed fit after a lower-leg injury, while Slater has been named at full-back but is still recovering from a knee injury aggravated against USA.Both sides boast 100% records heading into the encounter but Australia have not conceded a try since Josh Charnleys effort in their first pool match against England on the opening day.Aussie winger Jarryd Hayne is the competitions top try scorer with nine, closely followed by Tuivasa-Sheck with eight.But it is recently named Rugby League International Federation player of the year Sonny Bill Williams who has attracted the most interest in the tournament so far.The Kiwi - with a tournament high 17 offloads - has the chance of becoming the first player to win the World Cup in both rugby league and rugby union after triumphing with the All Blacks in 2011."Id give every award back in a heartbeat just to get across the line this weekend," said Williams.The (lack of) air up there Watch mCayman Islands-based Webb, the head of Fifas anti-racism taskforce, is in London for the Football Associations 150th anniversary celebrations and will attend Citys Premier League match at Chelsea on Sunday."I am going to be at the match tomorrow and I have asked to meet Yaya Toure," he told BBC Sport."For me its about how he felt and I would like to speak to him first to find out what his experience was."Uefa hasopened disciplinary proceedings against CSKAfor the "racist behaviour of their fans" duringCitys 2-1 win.Michel Platini, president of European footballs governing body, has also ordered an immediate investigation into the referees actions.CSKA said they were "surprised and disappointed" by Toures complaint. In a statement the Russian side added: "We found no racist insults from fans of CSKA." Baumgartner the disappointing news: Mission aborted.The supersonic descent could happen as early as Sunda.The weather plays an important role in this mission. Starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence.The balloon will slowly drift to the edge of space at 120,000 feet ( Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.They blew it in 2008 when they got caught cold in the final and they will not make the same mistake against the Kiwis in Manchester.Five years ago they cruised through to the final and so far history has repeated itself here - the last try they conceded was scored by Englands Josh Charnley in the opening game of the tournament.That could be classed as a weakness, a team under-cooked - but I have been impressed by the Kangaroos focus in their games since then.They have been concentrating on the sort of stuff that wins you tough, even contests - strong defence, especially on their own goal-line, completing sets and a good kick-chase. Theyve been great at all the unglamorous stuff that often goes unnoticed in the stands but not by your team-mates.It is as though their entire tournament has been preparation for the final.In Johnathan Thurston, Cooper Cronk, Cameron Smith and either Billy Slater or Greg Inglis at full-back they have a spine that is unmatched in rugby league. They have played in so many high-pressure games - a priceless asset going into Saturday.The Kiwis are a lot less experienced but winning a dramatic match like their semi-final against England will do wonders for their confidence.They defeated Australia in the Four Nations final in 2010 and the last World Cup, and know they can rise to the big occasion.（3）6