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How to solve 3 log8⁡〖X〗 +2logX〖8〗 = 7

User Terrel
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1 Answer

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D:x>0 \wedge x\\ot=1\\ D:x\in(0,1)\cup(1,\infty)\\\\ 3\log_8x+2\log_x8=7\\ 3\log_8x+2\cdot(1)/(\log_8x)=7\\ 3\log_8^2x+2=7\log_8x\\ 3\log_8^2x-7\log_8x+2=0\\ 3\log_8^2x-6\log_8x-\log_8x+2=0\\ 3\log_8x(\log_8x-2)-1(\log_8x-2)=0\\ (3\log_8x-1)(\log_8x-2)=0\\ 3\log_8x-1=0 \vee \log_8x-2=0\\ \log_8x^3=1 \vee \log_8x=2\\ x^3=8 \vee x=8^2\\ x=2 \vee x=64\\
User Gentatsu
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