Wednesday

April 16, 2014

April 16, 2014

Posted by **Rebekah** on Thursday, December 20, 2012 at 8:18pm.

the fact that this is x-1 and not + is really messing me up because i keep getting a negative number and that isnt possible

2. Solve: absolut value of(x^2 -4x-4) = 8

thanks so much!!! I have been studying and my final is tomorrow. these are just two questions that came up:)

- Precalc -
**Damon**, Thursday, December 20, 2012 at 10:02pmlog [ 4x/(2(x-1))] = 0

so

10^log [ 4x/(2(x-1))] = 10^0 = 1

so

4x/[2(x-1))] = 1

4x = 2 x - 2

2 x = - 2

x = -1

- Precalc -
**Damon**, Thursday, December 20, 2012 at 10:06pmx^2 - 4 x - 4 = 8

x^2 - 4 x - 12 = 0

solve quadratic

then other possible solution

x^2 - 4 x -4 = -8

x^2 - 4 x + 4 = 0

(x-2)(x-2) = 0

x = 2

- Precalc -
**Reiny**, Thursday, December 20, 2012 at 11:54pm1. I disagree with Damon's solution.

log(4x) = log2 + log(x-1) ,**so x>1**

log(4x) - log(x-1) = log2

log( 4x/(x-1) ) = log2

4x/(x-1) = 2

4x = 2x-2

2x = -2

x = -1 , but x > 1 or else log (4x) and log(x-1) are both undefined

no solution

- Precalc -
**Rebekah**, Friday, December 21, 2012 at 7:04amthanks so much both of you!! Yah I wasn't sure about the first one but now I know how to do both!!

thanks!!

**Related Questions**

Math Help Please - Which of the following expressions is equal to log (x sqrt-y...

math - Logarithm!!! Select all of the following that are true statements: (a) ...

Advanced Functions/ Precalculus Log - 1. Evaluate 4^(log base4 64) + 10^(log100...

Trigonometry - This is a logs question If u=x/y^2, which expression is ...

math(Please help) - 1) use the properties of logarithms to simplify the ...

TRig WIth LoGs help1!! - i have problem i can't solve and the book is no help.. ...

math - write as a single logarithm: -2logbase3(1/x)+(1/3)logbase3(square root of...

Math/trig - Log radical b/ a^2 is equivalent to 1) 1/2 log b + 1/2 log a 2) l/2 ...

Math - solve log(7x-3)+2log(5)=2+log(x+3) I've attempted to do this question ...

math - Q1:solve log(5)x-log(25)(x+10) = 0.5 Q2:If 2log(a)x=1+log(a) (7x-10a) ,...