Can someone show me how to solve this function to find t.
Please show all the steps so I can learn how to do this.
50=100-90(1/3)^t
50=100-90(1/3)^t how to solve for t?
2009-04-25 4:13 am
回答 (3)
2009-04-25 6:03 am
✔ 最佳答案
50 = 100 - 90(1/3)^t100 - 50 = 90(1/3)^t
90(1/3)^t = 50
(1/3)^t = 50/90
(1/3)^t = 5/9
log[(1/3)^t] = log(5/9)
(t)log(1/3) = log(5/9)
t = log(5/9)/log(1/3)
2009-04-25 11:19 am
First, subtract 100 from both sides, then divide by -90 to get:
(5/9) = (1/3)^t
Then take natural log on both sides to get
ln(5/9) = ln((1/3)^t) = t ln(1/3).
Dividing by ln(1/3), we find t = ln(5/9)/ln(1/3).
Logarithms help you "undo" exponentiation.
(5/9) = (1/3)^t
Then take natural log on both sides to get
ln(5/9) = ln((1/3)^t) = t ln(1/3).
Dividing by ln(1/3), we find t = ln(5/9)/ln(1/3).
Logarithms help you "undo" exponentiation.
2009-04-25 11:26 am
(1/3)^t=50/90=5/9
t Ln 1/3=Ln 5/9=====>
t=Ln 5/9 / Ln 1/3=0.535
===========================================
CHECK: 50=100-90(1/3)^0.535=100-50
t Ln 1/3=Ln 5/9=====>
t=Ln 5/9 / Ln 1/3=0.535
===========================================
CHECK: 50=100-90(1/3)^0.535=100-50
收錄日期: 2021-05-01 12:19:46
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090424201340AAYjP7n