Area between two curves

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Jun 2, 2021
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Calculate the area between two curves on interval [1,10]:

[math]y=\log_{10}(x)\,\,\,\,\,\wedge\,\,\,\,\,y=10^x\\\\A=\int_1^{10}(10^x-\log_{10}(x))dx=\left[\frac{10^x}{\ln(10)}-x\log_{10}(x)+\frac{x}{\ln(10)}\right]_1^{10}=...\\\\\text{Am I right? Or I'm completly stupid?}[/math]
 
Looks right to me.
I would rewrite the integrand using the change of base, so it's a bit nicer. Just personal preference, but ultimately arrive at the same answer.
[math]10^x-\log_{10}x=10^x-\frac{\ln x}{\ln 10}[/math][math]\int 10^x-\frac{\ln x}{\ln 10}=\int10^x\,dx - \frac{1}{\ln 10}\int \ln x\,dx=\frac{-x\ln x + 10^x +x}{\ln(10)}+C[/math]
 
Looks right to me.
I would rewrite the integrand using the change of base, so it's a bit nicer. Just personal preference, but ultimately arrive at the same answer.
[math]10^x-\log_{10}x=10^x-\frac{\ln x}{\ln 10}[/math][math]\int 10^x-\frac{\ln x}{\ln 10}=\int10^x\,dx - \frac{1}{\ln 10}\int \ln x\,dx=\frac{-x\ln x + 10^x +x}{\ln(10)}+C[/math]
Thank you Sir, you are my savior! :)
 
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