equation

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equation

by mariah » Mon Aug 03, 2009 12:11 pm
2^(-2x)-2^(-x)-6=0, 2^x=?
soryy dont have answers

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by tohellandback » Mon Aug 03, 2009 6:45 pm
2^(-2x)-2^(-x)-6=0

1/2^2x - 1/2^x - 6=0

a^2-a-6=0, where a=1/2^x

(a+2)(a-3)=0
a=-2 a=3

1/2^x cannot be equal to -2.
so,

1/2^x=3

2^x=1/3
The powers of two are bloody impolite!!