Question 1024928: Solve the following equation
log 7 + log(x − 1) − log(x^2 − 2) − log 2 = 0
I did [log 7x-7]-[log2x^2-4]=0
log(7x-7/2x^2-4)=0
10^0=7x-7/2x^2-4
1=7x-7/2x^2-4
multiplied both sides by (2x^2-4)
2x^2-4=7x-7
2x^2-7x-3=0
Am I doing this correct the answers i got were x=7+sqrt(73)/4 using quadratic formula. Thank you for your time! Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! Solve the following equation
log 7 + log(x − 1) − log(x^2 − 2) − log 2 = 0
I did [log 7x-7]-[log2x^2-4]=0
log(7x-7/2x^2-4)=0
10^0=7x-7/2x^2-4
1=7x-7/2x^2-4
multiplied both sides by (2x^2-4)
2x^2-4=7x-7
2x^2-7x-3=0 *********** It's good except it should be +3.
---------------
2x^2-7x+3=0
(2x-1)*(x-3) = 0
x = 3
x = 1/2 **** x = 1/2 --> log of negative number, not allowed.
