Logarithms help again!
Sorry guys this time I have more problems (if you know what I mean)...
-show all steps..
1)If x= A*sqrt of b/c, then logx is equal to...
2)log(base x+3)x+x-2/x=2
3)log2(x^2-1)=log(base 2)8, then solution set for x is
4)Solve for x to the nearest tenth: log(base x)5=3
5)Using Logarithms, solve the equation 3^2x=4 solve x to the nearest tenth
6)5^x=30 (solve for x to the nearest tenth)
7)5^3x=1000 (using log find the nearest tenth)
8)5^2w+9=40 (solve for w to the nearest hundreth)
thanks again! and don't forget to write the steps
February 15, 2011
5 Comments • Newest first
#4
log of x(5)=3
therefore
x^3=5
x= the cube root of 5
brb w/ calculator
k,
x=1.709975
#3
uhh let me edit
log2(x^2-1) =log base 2 (8)
log2(x^2-1) =3
therefore
2^3=x^2-1
8=x^2-1
9=x^2
3=x
I can't do #2 or #1 T_T
you should specify in number 2 where the parenthesis go. I always say base of x+3, then I evaluate with the parenthesis over the rest of that side of the equal side where the logarithm is applied.
[quote=RobCorso]6 is easy
log of base 5(30)= x
x= 2.1132827526
http://www.1728.com/logrithm.htm
7 is ok also
5^3x=1000
therefore
log of base 5 (1000)=3x
4.2920296742=3x
divide that by 3
1.430676
then round for both coz im too lazy too
(im in 8th grade im so proud of myself)
8:
5&2w+9=40
5^2w=31
log of base 5 (31)=2w
2.133656215=2w
1.066828=w[/quote]
I'm kind of embarrased that an 8th grader helped me >_> ~.. ( this is like 10th+ grade work)
#5
3^2x=4
log of base 3(4)=2x
1.2618595071=2x
0.63092975355=x
round it noa
1. Log x = log a + {(1/2)log b - (1/2)log c}
Can't give you numerical values since I don't know values of a,b, or c
BTW if its Log x, then the base is 10, since if it's not indicated, it's presumed to be 10
6 is easy
log of base 5(30)= x
x= 2.1132827526
http://www.1728.com/logrithm.htm
7 is ok also
5^3x=1000
therefore
log of base 5 (1000)=3x
4.2920296742=3x
divide that by 3
1.430676
then round for both coz im too lazy too
(im in 8th grade im so proud of myself)
8:
5^2w+9=40
5^2w=31
log of base 5 (31)=2w
2.133656215=2w
1.066828=w