一道高一数学对数运算题，急急急，在线等 高一数学对数计算，在线等，急！
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1)
lg25=2lg5
lg2*lg50
=lg2(2lg5+lg2)
原式=2lg5+2lg2lg5+2(lg2)^2
=2lg5+2(lg2+lg5)lg2
=2lg5+2lg2
=2lg10
=2
2)
√[(lg3)^2-lg9+1]
=√[(lg3)^2-2lg3+1]
=√(lg3-1)^2
=1-lg3
lg√27
=(3/2)lg3
lg8
=3lg2
lg√1000
=(3/2)lg10
=(3/2)
lg√27+lg8-lg√1000
=3lg√3+3lg2-3lg√10
=3lg√1.2
=(3/2)lg1.2
lg0.3
=(lg3-1)
原式=-1*(3/2)
=-3/2
16.(1)原式=lg25+lg2*(lg50+lg2)=2*lg5+2*lg2=2.
(2)原式=(1-lg3)*[(3/2)*lg3+3*lg2-3/2]/[(lg3-1)*(lg3+2lg2-1)]=-3/2
绛旓細2lg(5/3)-lg(7/4)+2lg3+(1/2)lg49 =lg(25/9)+lg9-(lg(7/4)-lg7)=lg25-lg(1/4)=lg(25*4)=lg100 =2.(lg2)^2+lg2lg5+lg50 =(lg2)^2+lg2lg5+lg5+lg10 =(lg2)^2+lg2lg5+lg5+1.=lg2*(lg2+lg5)+lg5+1 =lg2+lg5+1 =lg(2*5)+1 =2.lg(5^2)+2/...
绛旓細鑻og3 7路log2 9路log49 a=log4 1/2锛屽垯鏈夛細(lg7/lg3)路(lg9/lg2)路(lga/lg49)=lg(1/2)/lg4 鍗筹細(lg7/lg3)路(2lg3/lg2)路 lga/(2lg7)=-lg2/(2lg2)鍖栫畝寰楋細lga/lg2=-1/2 鍗筹細lga=(-1/2)lg2=-lg鏍瑰彿2=lg(鏍瑰彿2)/2 鎵浠ワ細a=(鏍瑰彿2)/2 ...
绛旓細鍘熷紡= lg(32/49)^1/2 - lg8^1/2*4/3 + lg7鈭5 = lg鈭32-lg鈭49-lg4+lg7+lg鈭5 =lg4鈭2-lg7-lg4+lg7+lg鈭5 =lg鈭2+lg鈭5 =lg鈭10 =1/2
绛旓細璁緇ogc(x)=m loga(x)=2,logb(x)=3,logabc(x)=12 loga(x)=logc(x)/logc(a)=2,logb(x)=logc(x)/logc(b)=3 logc(a)=logc(x)/2=m/2,logc(b)=logc(x)/3=m/3 鍙坙ogabc(x)=logc(x)/[logc(abc)]=m/[logc(a)+logc(b)+1]=12 m/[[m/2+m/3+1]=12 瑙ｅ緱:m=-...
绛旓細鍒嗗瓙=1+1/2*2lg3-lg40*6 =1+lg3-lg(4*10*6锛=1+lg3-2lg2-1-lg2-lg3 =-3lg2 鍒嗘瘝=1-2/3*3lg3+lg36-lg10/2 =1-2lg3+2lg6-1+lg2 =1-2lg3+2lg2+2lg3-1+lg2 =3lg2 鎵浠ユ瘮鍊兼槸-1
绛旓細瑙ｆ瀽 1锛宭g0.36=lg36/100=lg36-2=2lg6-2=2(lg2+lg3)-2=2*(0.3010+0.4771)-2=-0.4438 2,浠=5^20,涓よ竟鍙瀵规暟锛lgx=20lg5=20*(1-lg2)=13.98,鈭10^13锛渪锛10^14 鍗1000,000,000,000,0锛渪锛1000,000,000,000,00,鏁5^20涓14浣嶆暟 3锛屸埖y=x^2-1,鈭磝^2=y+1,鍙...
绛旓細鍏堟妸杩欎袱椤瑰叏閮ㄧ敤鎹㈠簳鍏紡鎹㈡垚鑷劧瀵规暟锛娑堟帀鍚湁3鐨勯」锛岀劧鍚庡啀鐢ㄦ崲搴曞叕寮忔崲鍥炲幓锛屽彉鎴恖og(2,4)锛岀瓟妗堝氨鏄2
绛旓細锛1锛塵lg2=nlg3=2lg6 1/m+1/n=(lg2+lg3)/2lg6=1/2 (2)xlg2=ylg5 x/y=lg5/lg2 (3)浠 alg3=blg4=clg6=m涓烘鏁 3a=3m/lg3 4b=4m/lg4 6c=6m/lg6 灏嗗垎瀛愭嬁涓嬫潵鏀惧叆lg绗﹀彿鍐咃紝鍙煡锛3a<4b<6c (4)鍘熷紡=锛坙gx/y锛/(1/2lg2)灏嗛璁捐В鏂圭▼锛寈/y=4 lg(x/y)=...
绛旓細鍏堣娓呮涓嬮潰 a^b 鎰忔濇槸 a鐨刡娆℃柟 瀵3^x=4^y=6^z姹俵n锛屾湁锛歺ln3=2yln2=zln6=zln2+zln3 璁緓ln3=a=2yln2=zln6=zln2+zln3 鍗虫湁锛1/x=ln3/a; 1/2y=ln2/a; 1/z=ln2/a + ln3/a;鍗宠瘉 鍙煡 8^p=3; 3^q=5;浠庤 (8^p)^q=5;5=8^(p*q)=2^(3*p*q...
绛旓細绛旀涓1 杩囩▼濡備笅鍥撅細
