2007-06-24 07:32:23 · 7 answers · asked by rediet t 1 in Science & Mathematics ➔ Mathematics
use the change of base formula to make log7 into ln
ln(1/49)/ln(7)= -X-2
add two to both sides
(ln(1/49)/ln(7))+2=-X
divide by -1
-(ln(1/49)/ln(7))-2=X
plug into calculator and you get X=0
2007-06-24 07:40:53 · answer #1 · answered by Kyle 3 · 0⤊ 0⤋
Log 7 1/49 = -X-2
=> 1/49 = 7^(-x-2)
=> 1/7^2= 7^(-x-2)
=> 7^-2= 7^(-x-2)
=>powers are equal
=>-2 = -x-2
=> x = 0
2007-06-24 14:43:10 · answer #2 · answered by harry m 6 · 1⤊ 0⤋
In the following, log means log to base 7:-
log (1/49) = - x - 2
log 7^(-2) = - x - 2
(-2) log 7 = - x - 2
-2 x 1 = - x - 2
- 2 = - x - 2
x = 0
2007-06-25 02:36:55 · answer #3 · answered by Como 7 · 1⤊ 0⤋
If you mean log(base7) of 1/49 = (-x-2), then 7^(-x-2) = 1/49.
To get 1/49, 7 must be raised to the power -2.
Ergo, (-x-2) = -2 â x = 0
2007-06-24 14:43:11 · answer #4 · answered by Steve 7 · 0⤊ 1⤋
x=0
2007-06-24 14:42:12 · answer #5 · answered by Anonymous · 0⤊ 1⤋
Is that log base 7 ?
2007-06-24 14:39:58 · answer #6 · answered by koutetsu12 3 · 0⤊ 1⤋
g
2014-08-25 06:07:56 · answer #7 · answered by Harneet 1 · 0⤊ 0⤋