



 
Hi Motaz. Let me demonstrate with a similar question: Let z = log_{5} (1/625). Start by realizing that if the log is in base 5, we want to exponentiate with base 5 on both sides: 5^{z} = 5^{ log5 (1/625)} On the right hand side, the exponentiation and the log cancel each other, because they have the same base of 5. So this simplifies to 5^{z} = 1/625 From here, it is just normal work with exponents: 5^{z} = 625^{1} Now you can do your question exactly the same way. Cheers,  


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