# Just need a little guidance on a part of a question.

• 03-25-2012, 10:58 AM
susu
Just need a little guidance on a part of a question.
1. Find the exact solution, using common logarithms, and a two-decimal-place approximation of each solution, when appropriate. of 3^(x+1)=2^(4-3x)

I got x= -(ln(3)+ln(2))/(ln(3)+3ln(2))
and finding the exact value is what's throwing me off. i keep getting -1.21810429

2.Solve the equation without using a calculator. log(x^4)=(log(x))^2
i got 1 as one of the answers but i'm not getting another value.

Thanks!
• 03-25-2012, 12:08 PM
Subhotosh Khan
Quote:

Originally Posted by susu
1. Find the exact solution, using common logarithms, and a two-decimal-place approximation of each solution, when appropriate. of

3^(x+1)=2^(4-3x)

(x+1) * ln3 = (4-3x) * ln2

x* ln3 + ln3 = 4*ln2 - x*3*ln2

x*(ln3+3ln2) = 4*ln2 - ln3

x = (4*ln2 - ln3)/(ln3+3ln2) ................this is

I got x= -(ln(3)+ln(2))/(ln(3)+3ln(2))
and finding the exact value is what's throwing me off. i keep getting -1.21810429

2.Solve the equation without using a calculator.

log(x^4)=(log(x))^2

4* log(x) = [log(x)]2

[log(x)]2 - 4* log(x) = 0

log(x) * [log(x) - 4] = 0

Now continue......

i got 1 as one of the answers but i'm not getting another value.

Thanks!

.