ĵ
ѡC
Ĺؼΰͼһһ֪õͼУҪҹɣϸѷ֣ͼͼ2+һӣ
10. ȸݡ1+2=90óEAM+EDNĶɽƽߵĶóEAF+EDFĶAEDEɵó3+4ĶɵóFAD+FDAĶڽǺͶɵóۣ 𡿽⣺ߡ1+2=90㣬 EAM+EDN=360-90=270㣮 ߡEAM͡EDNƽ߽ڵF EAF+EDF=AEDE 3+4=90㣬
FAD+FDA=135-90=45㣬
F=180-FAD+FDA=180-45=135㣮 ѡB
ڽǺͶֱεʼƽߵʣ֪εڽǺ͵180ǽĹؼ
1270=135㣮 2⣨6С⣬ÿС3֣18֣
11.Ӧжϳĵĺķţжڵޣ 𡿽⣺ߵPabڵޣ a0b0 b-a0a-b0
Mb-aa-bڵڶޣ
Ҫƽֱϵиĵķص㣮ĸķصֱǣһޣ++ڶޣ-+ޣ--ޣ+- 12. ݷȷ=ֵ-Сֵ㣮 𡿽⣺157-7610=8.1 80Ӧ9飬 ʴΪ9
ĵ
࣬ȷ=ֵ-СֵһӦСֵһӦֵ
13. ݵ㵽ֱߵľֱĵ봹߶εijȣɵô𰸣 𡿽⣺ACBC
ABCľΪ߶ACijȣ ʴΪAC
˵㵽ֱߵľ룬ֱһ㵽ֱߵĴ߶εijȣ㵽ֱߵľ룮
14. ֪ʽĽ⼯ȷʽ⼯ɣ 𡿽⣺߹xyĶԪһη??2x?my?5?x?3Ľ?
?x?ny?4?y?5stĶԪһη??2(s?t)?m(s?t)?5?s?t3?s4Ľ??
(s?t)?n(s?t)?4s?t5t?1???ʴΪ??s4
?t?1˶ԪһηĽ⣬ԼԪһη飬㷨ǽⱾĹؼ
15. εĸߣBEOAOFijԵóBC?AD=32
𡿽⣺BBExECCFyF
Bm3 BE=3 A40
ĵ
AO=4 Cn-5 OF=5
11AO?BE=43=6 2211SAOC=AO?OF=45=10
22SAOB=
SAOB+SAOC=6+10=16 SABC=SAOB+SAOC
1BC?AD=16 2BC?AD=32 ʴΪ32
ͼʣݵʾӦ߶εijڼоãҪգ߶εĻ 16. ݲʽȡ⼯ķȷaķΧɣ 𡿽⣺߲ʽ??1?x?5Ľ⼯Ϊax5
?a?x?a?3?1?a
a?3?5?ã2a5 ʴΪ2a5
˲ʽĽ⼯ղʽ⼯ķǽⱾĹؼ 17. 1ԭʽó˷壬ֵĴ壬Լ㼴ֵ
2üӼԪ⼴ɣ 𡿽⣺1ԭʽ=?1?2?3?3??????1??9?4?3 3?2x?3y12٣2?
3x?4y17?١3-ڡ2ãy=2 y=2ٵãx=3
ĵ
ĽΪ??x3 ?y2˽Ԫһη飬Լʵ㣬㷨ǽⱾĹؼ
18. 1ȥšϲͬϵΪ1ɵã
2ֱÿһʽĽ⼯ݿھͬȡͬСȡСССмҡССȷʽĽ⼯ 𡿽⣺16-2x-23x-6 -2x-3x-6-6+2 -5x-10 x2
2ⲻʽx3x-2+4ãx1 ⲻʽ
2xx?1ãx-5 ?1?52ʽĽ⼯Ϊ-5x1
ԸòʽΪ-4-3-2-101
ǽһԪһβʽ飬ȷÿһʽ⼯ǻ֪ͬȡͬСȡСССмңССҲԭǽĹؼ 19. 1AC꽨ֱϵ
2õAĶӦD꣬ȷƽƵķ;룬ôƽƹдEF꣬Ȼ㼴ɣ
3ã2еƽƹɷƽƿдQ꣮ 𡿽⣺1ͼʾֱϵ 2ͼDEFΪ