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1) ![2log_{0,1}(6)-log_{0,1}(100)+3log_{0,1} sqrt[3]{20} =log_{0,1}( frac{6^2}{100}*( sqrt[3]{20} )^3 )= 2log_{0,1}(6)-log_{0,1}(100)+3log_{0,1} sqrt[3]{20} =log_{0,1}( frac{6^2}{100}*( sqrt[3]{20} )^3 )=](https://tex.z-dn.net/?f=2log_%7B0%2C1%7D%286%29-log_%7B0%2C1%7D%28100%29%2B3log_%7B0%2C1%7D+sqrt%5B3%5D%7B20%7D+%3Dlog_%7B0%2C1%7D%28+frac%7B6%5E2%7D%7B100%7D%2A%28+sqrt%5B3%5D%7B20%7D+%29%5E3+%29%3D)
![=log_{0,1}( frac{36*20}{100} )=log_{0,1}( frac{36}{5} )=log_{0,1}(7,2)=-lg(7,2) =log_{0,1}( frac{36*20}{100} )=log_{0,1}( frac{36}{5} )=log_{0,1}(7,2)=-lg(7,2)](https://tex.z-dn.net/?f=%3Dlog_%7B0%2C1%7D%28+frac%7B36%2A20%7D%7B100%7D+%29%3Dlog_%7B0%2C1%7D%28+frac%7B36%7D%7B5%7D+%29%3Dlog_%7B0%2C1%7D%287%2C2%29%3D-lg%287%2C2%29)
2)![4log_{0,1}(3)-2/3*log_{0,1}(27)-2log_{0,1}(6)=log_{0,1} (frac{3^4}{ sqrt[3]{27^2}*6^2 } )= 4log_{0,1}(3)-2/3*log_{0,1}(27)-2log_{0,1}(6)=log_{0,1} (frac{3^4}{ sqrt[3]{27^2}*6^2 } )=](https://tex.z-dn.net/?f=4log_%7B0%2C1%7D%283%29-2%2F3%2Alog_%7B0%2C1%7D%2827%29-2log_%7B0%2C1%7D%286%29%3Dlog_%7B0%2C1%7D+%28frac%7B3%5E4%7D%7B+sqrt%5B3%5D%7B27%5E2%7D%2A6%5E2+%7D+%29%3D)
![=log_{0,1}( frac{81}{9*36} )=log_{0,1}( frac{81}{9*9*4} )=log_{0,1}( frac{1}{4} )=-lg( frac{1}{4} )=lg(4) =log_{0,1}( frac{81}{9*36} )=log_{0,1}( frac{81}{9*9*4} )=log_{0,1}( frac{1}{4} )=-lg( frac{1}{4} )=lg(4)](https://tex.z-dn.net/?f=%3Dlog_%7B0%2C1%7D%28+frac%7B81%7D%7B9%2A36%7D+%29%3Dlog_%7B0%2C1%7D%28+frac%7B81%7D%7B9%2A9%2A4%7D+%29%3Dlog_%7B0%2C1%7D%28+frac%7B1%7D%7B4%7D+%29%3D-lg%28+frac%7B1%7D%7B4%7D+%29%3Dlg%284%29)
46. а)![sqrt{x+2}*log_3(x)=0 sqrt{x+2}*log_3(x)=0](https://tex.z-dn.net/?f=+sqrt%7Bx%2B2%7D%2Alog_3%28x%29%3D0+)
Область определения x > 0, поэтому x = -2 не подходит.
x = 1;![log_3(1)=0 log_3(1)=0](https://tex.z-dn.net/?f=log_3%281%29%3D0)
б)![sqrt{x}*log_3(x+2)=0 sqrt{x}*log_3(x+2)=0](https://tex.z-dn.net/?f=sqrt%7Bx%7D%2Alog_3%28x%2B2%29%3D0)
Область определения x > -2, поэтому
x1 = 0; x + 2 = 1; x2 = -1
45. а)![log_2^2(x)+log_2(x^2)=-1 log_2^2(x)+log_2(x^2)=-1](https://tex.z-dn.net/?f=log_2%5E2%28x%29%2Blog_2%28x%5E2%29%3D-1)
![log_2^2(x)+2log_2(x)+1=(log_2(x)+1)^2=0 log_2^2(x)+2log_2(x)+1=(log_2(x)+1)^2=0](https://tex.z-dn.net/?f=log_2%5E2%28x%29%2B2log_2%28x%29%2B1%3D%28log_2%28x%29%2B1%29%5E2%3D0)
![log_2(x)=-1; x=2^{-1}=1/2 log_2(x)=-1; x=2^{-1}=1/2](https://tex.z-dn.net/?f=log_2%28x%29%3D-1%3B+x%3D2%5E%7B-1%7D%3D1%2F2)
x = 1/2
б)![log_4^2(x)+log_4( sqrt{x} )=1,5 log_4^2(x)+log_4( sqrt{x} )=1,5](https://tex.z-dn.net/?f=log_4%5E2%28x%29%2Blog_4%28+sqrt%7Bx%7D+%29%3D1%2C5)
![log_4^2(x)+0,5log_4( x)-1,5=0,5(log_4( x)-1)(2log_4( x)+3)=0 log_4^2(x)+0,5log_4( x)-1,5=0,5(log_4( x)-1)(2log_4( x)+3)=0](https://tex.z-dn.net/?f=log_4%5E2%28x%29%2B0%2C5log_4%28+x%29-1%2C5%3D0%2C5%28log_4%28+x%29-1%29%282log_4%28+x%29%2B3%29%3D0)
![log_4(x)=1; x1=4 log_4(x)=1; x1=4](https://tex.z-dn.net/?f=log_4%28x%29%3D1%3B+x1%3D4)
![log_4(x)=-3/2;x2=4^{-3/2}= frac{1}{4^{3/2}} = frac{1}{2^3} = 1/8 log_4(x)=-3/2;x2=4^{-3/2}= frac{1}{4^{3/2}} = frac{1}{2^3} = 1/8](https://tex.z-dn.net/?f=log_4%28x%29%3D-3%2F2%3Bx2%3D4%5E%7B-3%2F2%7D%3D+frac%7B1%7D%7B4%5E%7B3%2F2%7D%7D+%3D+frac%7B1%7D%7B2%5E3%7D+%3D+1%2F8)
x1 = 4; x2 = 1/8
47. а)![lg(10x^2)*lg(x)=1 lg(10x^2)*lg(x)=1](https://tex.z-dn.net/?f=lg%2810x%5E2%29%2Alg%28x%29%3D1)
![(lg(10)+lg(x^2))*lg(x)=(1+2lg(x))*lg(x)=1 (lg(10)+lg(x^2))*lg(x)=(1+2lg(x))*lg(x)=1](https://tex.z-dn.net/?f=%28lg%2810%29%2Blg%28x%5E2%29%29%2Alg%28x%29%3D%281%2B2lg%28x%29%29%2Alg%28x%29%3D1)
![2lg^2(x)+lg(x)-1=(lg(x)+1)(2lg(x)-1)=0 2lg^2(x)+lg(x)-1=(lg(x)+1)(2lg(x)-1)=0](https://tex.z-dn.net/?f=2lg%5E2%28x%29%2Blg%28x%29-1%3D%28lg%28x%29%2B1%29%282lg%28x%29-1%29%3D0)
lg x = -1; x1 = 0,1; lg x = 1/2; x2 = 10^(1/2) = √10
Ответ: x1 = 0,1; x2 = √10
б)![lg(0,1x^2)*lg(x)=1 lg(0,1x^2)*lg(x)=1](https://tex.z-dn.net/?f=lg%280%2C1x%5E2%29%2Alg%28x%29%3D1)
![(lg(0,1)+lg(x^2))*lg(x)=(-1+2lg(x))*lg(x)=1 (lg(0,1)+lg(x^2))*lg(x)=(-1+2lg(x))*lg(x)=1](https://tex.z-dn.net/?f=%28lg%280%2C1%29%2Blg%28x%5E2%29%29%2Alg%28x%29%3D%28-1%2B2lg%28x%29%29%2Alg%28x%29%3D1)
![2lg^2(x)-lg(x)-1=(lg(x)-1)(2lg(x)+1)=0 2lg^2(x)-lg(x)-1=(lg(x)-1)(2lg(x)+1)=0](https://tex.z-dn.net/?f=2lg%5E2%28x%29-lg%28x%29-1%3D%28lg%28x%29-1%29%282lg%28x%29%2B1%29%3D0)
lg x = 1; x1 = 10; lg x = -1/2; x2 = 10^(-1/2) = 1/10^(1/2) = 1/√10
Ответ: x1 = 10; x2 = √10/10
Всё!
2)
46. а)
Область определения x > 0, поэтому x = -2 не подходит.
x = 1;
б)
Область определения x > -2, поэтому
x1 = 0; x + 2 = 1; x2 = -1
45. а)
x = 1/2
б)
x1 = 4; x2 = 1/8
47. а)
lg x = -1; x1 = 0,1; lg x = 1/2; x2 = 10^(1/2) = √10
Ответ: x1 = 0,1; x2 = √10
б)
lg x = 1; x1 = 10; lg x = -1/2; x2 = 10^(-1/2) = 1/10^(1/2) = 1/√10
Ответ: x1 = 10; x2 = √10/10
Всё!
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