2010. . B4.
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.: ; 2010, 48 .
2010. 2010 . -2010.
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http://geometry2006.narod.ru/
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1.1. ABC C 90, AB = 10, AC = 8. sin A.
1.2. ABC C 90, sin A = 0,6. cos A.
1.3. ABC C 90, CH 6, AC = 10. tg A.
2.1. ABC AC = BC = 10, AB = 12. sin A.
2.2. ABC AC = BC, AB = 10, AH 8. cos A.
2.3. ABC AB = BC, CH 8, AC = . ACB.
3.1. ABC C 90, AB = 10, BC = 6. A.
3.2. ABC C 90, sin A = 0,6. A.
3.3. ABC C 90, AB = 10, AC = 8. A.
4.1. AOB. , .
4.2. AOB.
4.3. AOB. , .
5.1. ABC C 90, BC = 4, sin A = 0,8. AB.
5.2. ABC C 90, tg A = 0,75, AC = 8. AB.
5.3. ABC C 90, CH , BC = 6, cos A = 0,8. CH.
6.1. ABC AC = BC = 10, sin A = 0,8. AB.
6.2. ABC AC = BC, AB = 10, cos A = 0,6. AH.
6.3. ABC AB = BC, CH 5, tg C = . AC.
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1.1. . ABC AB 10. BC. , BC = . , sin A = 0,6.
. AC 8, AB 10, cos A = 0,8. , . sin A = 0,6.
. 0,6.
1.2. . . cos A = = 0,8.
. , AB BC 10 6. AC 8 , , cos A = 0,8.
. 0,8.
1.3. ACH CH 6, AC 10. , AH = 8. , tg A = 0,75.
. 0,75.
2.1. CH. ACH AC 10, AH 6. CH = 8 , , sin A = 0,8.
. 0,8.
2.2. ABH AB 10, AH 8. BH = 6 , , cos B = 0,6. A B ABC , cos A = 0,6.
. 0,6.
2.3. ACH AC , CH 8. AH. AH = = 16. tg A = 0,5. A C ABC , ACB 0,5.
. 0,5.
3.1. A ABC A , , 0,6.
. 0,6.
3.2. A cos A. , . cos A = = 0,8 , , A 0,8.
. 0,8.
3.3. A tg A. BC = = 6 , , tg A = 0,75. , A 0,75.
. 0,75.
4.1. . OBC. BC 3, OB . , sin A = .
. AOB 45. , sin A = .
. 2.
4.2. OBC. BC OC 4 2. , BOC 2. , , , , AOB 2.
. 2.
4.3. OB. OC = BC = , OB = . , OBC , AOB .
. 2.
5.1. BC = AB sin A BC sin A, AB = 5.
. 5.
5.2. BC = AC tg A = 8 0,75 = 6. AB = = 10.
. 10.
5.3. BCH BAC , , , cos BCH = 0,8. CH = BC cos BCH = 4,8.
. 4,8.
6.1. . CH. CH = AC sin A = 8. AH = , , AB = 12.
. CH. , . cos A = = 0,6. , AH = AC cos A = 6 , , AB = 12.
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. 12.
6.2. . ABC A B, BH = AB cos B = 6. AH = .
. , . sin A = = 0,8. , A = B, AH = AB sin B = 8.
. 8.
6.3. . ABC A C,, tg A = tg C AH = . AC = = 10.
. tg C = , C 30. A C. , 30, , AC = 10.
. 10.
1.
1. ABC C 90, AB = 10, BC = 6. cos A.
2. ABC C 90, AB = 10, AC = 8. tg A.
3. ABC C 90, cos A = 0,8. sin A.
4. ABC C 90, cos A = 0,8. tg A.
5. ABC C 90, tg A = 0,75. sin A.
6. ABC C 90, sin A = 0,6. cos B.
7. ABC C 90, cos A = 0,8. sin B.
8. ABC C 90, CH , AC = 10, AH = 8. cos B.
9. ABC C 90, CH , BC = 10, BH = 6. cos A.