1.若2的6a次方=3的3b次方=6的2a次方,求证:3ab-2ac=bc2.已知lga+|lgb|=-2,|lga|+lgb=-3,求a与b的值3.设a,b,c是三角形ABC的三边,且a不等于1,b小于c,若log(c+b)底a+log(c-b)底a=2log(c+b)底a*log(c-b)底a,判断三角形A
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![1.若2的6a次方=3的3b次方=6的2a次方,求证:3ab-2ac=bc2.已知lga+|lgb|=-2,|lga|+lgb=-3,求a与b的值3.设a,b,c是三角形ABC的三边,且a不等于1,b小于c,若log(c+b)底a+log(c-b)底a=2log(c+b)底a*log(c-b)底a,判断三角形A](/uploads/image/z/14410033-25-3.jpg?t=1.%E8%8B%A52%E7%9A%846a%E6%AC%A1%E6%96%B9%3D3%E7%9A%843b%E6%AC%A1%E6%96%B9%3D6%E7%9A%842a%E6%AC%A1%E6%96%B9%2C%E6%B1%82%E8%AF%81%EF%BC%9A3ab-2ac%3Dbc2.%E5%B7%B2%E7%9F%A5lga%2B%EF%BD%9Clgb%EF%BD%9C%3D-2%2C%EF%BD%9Clga%EF%BD%9C%2Blgb%3D-3%2C%E6%B1%82a%E4%B8%8Eb%E7%9A%84%E5%80%BC3.%E8%AE%BEa%2Cb%2Cc%E6%98%AF%E4%B8%89%E8%A7%92%E5%BD%A2ABC%E7%9A%84%E4%B8%89%E8%BE%B9%2C%E4%B8%94a%E4%B8%8D%E7%AD%89%E4%BA%8E1%2Cb%E5%B0%8F%E4%BA%8Ec%2C%E8%8B%A5log%28c%2Bb%29%E5%BA%95a%2Blog%28c-b%29%E5%BA%95a%3D2log%28c%2Bb%29%E5%BA%95a%2Alog%28c-b%29%E5%BA%95a%2C%E5%88%A4%E6%96%AD%E4%B8%89%E8%A7%92%E5%BD%A2A)
1.若2的6a次方=3的3b次方=6的2a次方,求证:3ab-2ac=bc2.已知lga+|lgb|=-2,|lga|+lgb=-3,求a与b的值3.设a,b,c是三角形ABC的三边,且a不等于1,b小于c,若log(c+b)底a+log(c-b)底a=2log(c+b)底a*log(c-b)底a,判断三角形A
1.若2的6a次方=3的3b次方=6的2a次方,求证:3ab-2ac=bc
2.已知lga+|lgb|=-2,|lga|+lgb=-3,求a与b的值
3.设a,b,c是三角形ABC的三边,且a不等于1,b小于c,若log(c+b)底a+log(c-b)底a=2log(c+b)底a*log(c-b)底a,判断三角形ABC形状
解一条是一条
1.若2的6a次方=3的3b次方=6的2a次方,求证:3ab-2ac=bc2.已知lga+|lgb|=-2,|lga|+lgb=-3,求a与b的值3.设a,b,c是三角形ABC的三边,且a不等于1,b小于c,若log(c+b)底a+log(c-b)底a=2log(c+b)底a*log(c-b)底a,判断三角形A
给你做一下吧,搞这么多,呵呵
1.若2^6a=3^3b=6^2c,求证:3ab-2ac=bc
证明:设2^6a=3^3b=6^2c=t,则:log(2)t=6a;log(3)t=3b;log(6)t=2c
即:log(t)2=1/6a log(t)3=1/3b log(t)6=1/2c
而:log(t)6=log(t)2+log(t)3
所以:1/6a +1/3b =1/2c
即:3ab-2ac=bc
2.这个题目有问题哦,你看看:
由lga+|lgb|=-2 可知lga
用换底的方法做就好做了