3 - sin70¡ã 2 - cos 2 10¡ã =

3-sin70¡ã 2-co s 2 10¡ã = 3-sin70¡ã 2- 1+cos20¡ã 2 = 2(3-sin70¡ã) 3-co s 20¡ã = 2(3-cos20¡ã)...

(3 - 70¡óµÄÕýÏÒ)/(2 - 10¡óÓàÏÒÆ½·½)µÄ±ÈֵΪ?

3-sin70¡ã=3-sin(90¡ã-20¡ã)=3-cos20¡ã =3-(1+cos10¡ãµÄƽ·½)=2-cos10¡ãµÄƽ·½ ËùÒÔ£¬±ÈֵΪ1

(3 - sin70¡ã)/(2 - cos²10¡ã)µÈÓÚ¶àÉÙ?ÇóÏê½â,

(3-sin70¡ã)/(2-cos²10¡ã)=(3-cos20º)/(2-cos²10º)=[3-(2cos²10º-1)]/(2-cos²10º)=(4-2cos&#...

¸ßÒ»ÊýѧÈý½Çº¯Êý1.cot30¡ãcos10¡ã+¸ùºÅ3sin70¡ãtan70...

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sin10¶È*sin50¶È*sin70¶ÈÔõôÇó?

70)4sin3(70)=sin210=12Òò´Ë£¬

3 - sin70¶È±ÈÉÏ2 - cosƽ·½10¶È Çó½â´ð

2011-03-01 3-sin70(¶È) ËüÊÇ·Öĸ ¡ª¡ª¡ª 2-cos10(... 2 2011-08-09 2sin20¶È+2(cos5¶È)µÄƽ·½+(cos70¶È³Ësi... 2 2016...

sin70¶ÈÊÇÌØÊâ½Çô?Ôõô¼ÆËã?

sin70¶È²»ÊÇÒ»¸öÌØÊâ½Ç£¬Æä¼ÆËã½á¹ûÈçÏÂͼ£ºÔÚÈý½Çº¯ÊýÖУ¬ÓÐÒ»Ð©ÌØÊâ½Ç£¬ÀýÈç30¡ã¡¢45¡ã¡¢60¡ã£¬ÕâЩ½ÇµÄÈý½Çº¯ÊýֵΪ¼òµ¥µ¥Ïîʽ£¬¼ÆËãÖÐ...

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²»²é±íÇó2sin70¶È+cos10¶È(1 - ¸ùºÅ3tan10¶È)/cos25¶ÈµÄ...

2sin70+cos10(1-3^0.5tan10)=2sin70+cos10-3^0.5sin10=2sin70+2(0.5cos10-3^0.5/2sin10)=2sin70+2sin20=4sin45cos25=2*2^0.5cos25ËùÒÔԭʽ»¯¼òΪ2*2^...

3 - sin70¡ã/2 - cos10¡ã=

=2(3-sin70¡ã)/(4-2cos²10¡ã) £¨¶þ±¶½Ç¹«Ê½£©=2(3-sin70¡ã)/(4-cos20º-1)=2(3-sin70¡ã)/(3-cos20¡ã)=2(3...

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