Very silly question on whether the domain of ##log_{10}(x²)## = ##2log_{10}(x)##

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SUMMARY

The domain of the function $$log_{10}(x²)$$ is confirmed to be the same as that of $$2log_{10}(|x|)$$, which is defined for all non-zero real numbers. The x-intercepts for both forms are found to be x = {-1, 1} for $$log_{10}(x²)$$ and x = {1} for $$2log_{10}(x)$$. However, the correct interpretation of the simplified form is $$2log_{10}(|x|)$$, which retains the x-intercepts of the original function.

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So say I have to find the x intercept of this function $$log_{10}(x²)$$ I get x={-1,1}.
But if I try to find the x intercept of this same function after simplifying I get $$2log_{10} (x)$$ I get x={1}
 
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tellmesomething said:
Homework Statement: Title
Relevant Equations: Title

So say I have to find the x intercept of this function $$log_{10}(x²)$$ I get x={-1,1}.
But if I try to find the x intercept of this ## same function## after simplifying I get $$2log_{10} (x)$$ I get x={1}
After simplifying, you get ##2log_{10} (|x|)## rather than ##2log_{10} (x)##, which has the same intercept as the original function.
 
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Hill said:
After simplifying, you get ##2log_{10} (|x|)## rather than ##2log_{10} (x)##, which has the same intercept as the original function.
Okay then :-)
 

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