The Purplemath Forums

by **triplesports17** on Fri Feb 13, 2009 6:09 am

If i am taking the dot product of for example < e^(x) , sqrt(2) , -e^(-x) > DOT < e^(x) , 0 , e^(-x) >

when i am multiplying the e^x terms do they become 2e^x or do they become e^(2x)... I cannot remember.

Thanks

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by **DAiv** on Fri Feb 13, 2009 11:14 am

triplesports17 wrote:when i am multiplying the e^x terms do they become 2e^x or do they become e^(2x)... I cannot remember.

$e^x \,+\, e^x \,=\, 2 (e^x) \,=\, 2e^x$
$(e^x)(e^x) \,=\, (e^x)^2 \,=\, e^{2x}$

If you're unsure in future, try an example with actual numbers:

$(2^3)(2^3) \,=\, (8)(8) \,=\, 64 \,=\, 2^6 \,=\, 2^{(2)(3)}$

DAiv

The Purplemath Forums

Please refresh my memory on exponential stuff

Please refresh my memory on exponential stuff

Re: Please refresh my memory on exponential stuff