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#1 2006-11-20 04:37:56

Kiran
Member
Registered: 2006-11-15
Posts: 177

Next

solve for x

log4 (x - 1) + log4 (x + 2) = 1
log4 (x - 1) (x + 2) = 1
(x - 1)(x + 2) = 4^1
now what?


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#2 2006-11-20 04:39:15

Toast
Real Member
Registered: 2006-10-08
Posts: 1,321

Re: Next

Well, you've done the hard part already, just solve it as a normal quadratic now. Make one side of the equation equal to zero and use factorisation and the null factor law or the quadratic formula.

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#3 2006-11-20 15:35:38

basmah
Member
Registered: 2006-10-02
Posts: 18

Re: Next

yup, now just multiply and you get:

x²+2x-x-2=4
x²+x-2-4=0
x²+x-6=0
(x-2)(x+3)=0
x=2 and x=-3 are the solutions

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