Question 1068111: Write as a single logarithm?
4*log3+log2
Solve. Give BOTH the exact answer and approximate answer for x?
20^x = e^x+a
How long will it take for the balance of an account to double if the savings account earns 0.75% annual interest compounded monthly?
Set up the problem using the formula: A=P(1+r/n)^nt
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! Two of them:
4*log3+log2
log 3^4 +log 2
log (81*2)
log (162) ANSWER
check
4 log 3=1.91
log 2=0.30
2.21 is the sum
log 162=2.21
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P=Po(1+(.0075/12)^t
P/Po=2, since it doubles
2=(1+.000625)^t
ln2=t ln (1.000625)
t=ln 2/ln(1.000625)=1109.38 interest compoundings, 12 a year
divide by 12 to get years, and 92.45 years. Rule of 70 says divide 70 by interest rate in per cent to get doubling time in years. 70/.75=93.3 years
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Here, x and a will vary. If x=0, a=0, if x=1, a =about 17.3, if x=2, a= about 390, if x=-1, a=-0.32
20^x=e^x+a
x ln 20=ln(e^x+a)
ln 20=[ln (e^x+a)]/x
raise to e power
20=(e^x+a)/e^x
20 e^x=(e^x+a)
19 e^x=a
e^x=(a/19)
x=ln(a/19)=ln a- ln 19, that is (2.94)
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