sin60cos60cos120cos240cos48011．解：（1）原式?sin6cos12cos24cos48? 0cos6000011sin120cos120cos240cos480sin240cos240cos480?2?40cos6cos60
111sin480cos480sin960cos6011616?8???cos60cos60cos60161?cos4001?cos10001??(sin700?sin300) （2）原式?222111?1?(cos1000?cos400)?sin700?
224?313?sin700sin300?sin700? 424212．解：令cos??cos??t，则(sin??sin?)?(cos??cos?)21?t2?,
2132?2cos(???)?t2?,2cos(???)?t2?
22?2?t2?3171414 ?2,??t2?,??t?222222213．解：2(2cosB?1)?8cosB?5?0,4cosB?8cosB?5?0
??a?b3413 得cosB?,sinB?，cos??????,sin??,
5522a?b sin(B??)?sinBcos??cosBsin??4?33 1014．解：f(x)?13a3asin2x?(1?cos2x)?a?b 222 16
?a3a?sin2x?cos2x?b?asin(2x?)?b 223 （1）2k???2?2x??3?2k??3?5?11?,k???x?k?? 21212 ?[k??5?11?,k??],k?Z为所求 1212 （2）0?x??2,??3?2x??3?2?3?,??sin(2x?)?1 323 f(x)min??3a?b??2,f(x)max?a?b?3, 2?3?a?2a?b??2????? ?2 ??b??2?3?a?b?3?练习八
????????2811.A 2.B 3.A 4.C 5.C 6. k?? 7. 120° 8. AD?BC?? 9. 10. 12
33311.解设?AOC??
1?????????????????????????cos??x?y????OC?OA?xOA?OA?yOB?OA,2 ????????????????，即??????????1??cos(1200???OC?OB?xOA?OB?yOB?OB,)??x?y??2∴x?y?2[cos??cos(120??)]?cos??3sin??2sin(??0?6)?2
??3312.解（1）?a||b ，∴cosx?sinx?0，∴tanx??
222cos2x?2sinxcosx2?2tanx2022cosx?sin2x???. 222sinx?cosx1?tanx13??1（2）?a?b?(sinx?cosx,)
2
17
???2?f(x)?(a?b)?b?sin(2x?)
24?3????2?2x??，∴?1?sin(2x?)?∵??x?0，∴?
244442?2121??,? 函数 f(x)的值域为?f(x)? ∴?22?22??????????????????13. 解 （1）由题意知AB?BC?|AB|?|BC|cos??6.
??????????1????1???16?3tan?; S?|AB||BC|sin(???)?|AB|?|BC|sin???222cos??3?S?33,即3?3tan??33，
?? ?1?tan??3,又???[0,?]???[?]
4322（2）f(?)?sin??2sin?cos??3cos??1?sin2?
?2cos2??2?sin2??cos2?
??2?2sin(2??)
4???3?11????[,],?2???[?]
434412?3???当2???,即??时，f(?)最大，其最大值为3.
444????????14. 解: (1)AB?(n?8,t),?AB?a?8?n?2t?0
∴?????????? 又?5|OB|?|AB|,?5?64?(n?3)2?t2?5t2,得t??8 ???????? ?OB?(24,8)或OB?(?8,?8)
????(2)AC?(ksin??8,t)
???? ?AC与a向量共线, ?t??2ksin??16
k32?tsin??(?2ksin??16)sin???2k(sin??)2?
4k?k?4,?1?kk32?0,?当sin??时，tsin?取最大值为 44k 18
32??????4，得k?8，此时??,OC?(4,8) 由k6?????????OA?OC?(8,0)?(4,8)?32
英 语
练习一
一． 单项选择 DDCBC/ CDBCC/DABDA 二． 完型 CDBBC/ADACD/BCADB/DACBA 三． 阅读理解：A篇 CBCDD 词义猜测 CABDA
B篇 ADBCD 填空 quarrels/nasty/sayings/mood/actually 四． 单词upset/recover/grateful/concern/ignored/settled/official 五． 改错 1.high→highly 2.are→ is 3.produce →produces 4. ∧produce ;to 5. purpose
→purposes 6.∧country; a 7. or→and 8. cheap→expensive 9. on---to 10. the coal→coal
练习二
一． 单项选择CABAB/ACBBC/CBACA 二． 完形 CCBDB/ACCBA/CBDAD/ABDAC 三． 阅读理解：A篇 BBCDA 词义猜测 DCBCA
B篇 DDBBC 填空 gradually/improve/express/patient/achievement 四． 单词cycle/forecast/extreme/buried/frightening/event/fare
五．改错 1. that→when 2. their--its 3.Short →Shortly /Soon/Immediately4. was →had /happened→happening 5. shoes →shoe 6.cry前加 a/cry→crying 7. On→At 8. apologize后加 to 9. 去掉 had 10. after→before
练习三
一． 单项选择CACBD/DABDB/DDBCB/CCCDB 二． 完形 BCAAD/DADBB/ADABC/CBDCA 三． 阅读理解：A篇 BCCBB 词义猜测 CDABA
B篇 BDCDD 填空 pursuit/shepherds/distance/caught sight of/cubs 四． 单词surely/principle/equal/violence/instruction/abnormal/survived
五．改错1．has—is 2．去掉the 3．graduated后加from 4．becomes—became 5．taught—teaching 6．Succeed---successful
7．honor—honors 8．speaks 9．Collecting 10．music前加to
练习四
一． 单项选择 DBADB/ACDCB/CCCCA/AABAC 二． 完形 ACBDB/ADBCD/CBACD/DACCB 三． 阅读理解：A篇 BABC B篇 BBBAC
四．单词compete/volunteers/nowadays/replaced/universal/advertise/bargaining
五．1.pleased 后加was 2. and→but 3.something →anything 4.week→weeks 5.badly→bad 6.am→were 7.Its→It?s 8.去掉第二个to 9.decided→decide 10.get→getting
19
英语练习五 一． 单项选择ADBBC/ BABBB/ DBAAC/ CDCCB 二． 完形 BAADA/CBDAB/CBCCA/DCDBD 三．阅读理解：A篇 BACBC B篇 BCDCA
四．单词wildlife/succeeded/stable/pretended/amount/witness/reduce 五．改错1．wake改为woke / waked 2.out改为out of 3.extreme改为extremely 4.at改为till / until 5.a改为the 6.themselves改为itself7.because of改为because 8.That改为It 9.I改为me 10. help sb. do sth.
物 理
练习一
1．AD 2．AC 3．D 4．ABD 5．B 6．D 7．AD 8．B 9.A 10.AD 11.AC 12.B 13.A 14.AD 15.B 16．9.44m/s 17．12.5m 18．（3?2）：（2?1）：1 19．v0?6a(s?l) 20．1.125 21 . 24． a =
2h(t1?t2)3-3 22. 23． 9/8
t2t1(t1?t2)2L2?L1 25. 1800m 92.6s 26．解：（1）h=99 m ；（2）t总=t1+t2=8.6 (s) 22t27（1）如果采用匀加速，在火车到达交叉点之间冲过去，加速度a?0.6m/s2；（2）如果采用匀减速，汽车达到交叉时，火车恰好已过交叉点，加速度a?0.3m/s2
练习二
1．AC 2．D 3．D 4．BD 5．A 6．D 7．BC 8．B 9．B 10．B 11．B 12．BC 13．A 14．B 15．C
v216．2:1 3:1 17．略 18．f=0；F＇＝40N 19．F=(M+2m)?g的向右水平力；A至少长
2?g20． 21．36m 22．0.25 0.84kg/s
练习三
1．D 2．B 3．C 4．C 5．A 6．C 7．B 8．C 9．B 10．BD 11．D 12．C 13．D 14．A 15．CD 16．AD 17．9N 0 18． 0.72s 19．0.225 0.500 20． 500 不变 减小 21．略 22．（1）μ=0.75 （2）f1︰f2=4︰3 23．（1）t=200s （2）v=10m/s 24．(1)15N (2) 15N 25．(1)α=300 (2)μ=0.2 (3)v=2.3m/s
练习四
1．B 2．CD 3．CD 4．AD 5．BD 6．C 7．B 8．D 9．ACD 10．B 11．A 12．C 13．C 14．BD 15．AC 16．6.25s 17．18m 18．（1）手感觉不到铅球的压力 （2）135.7N 19．（1）X=k FL/S （2） Fmax=1×104N
化 学
20