This week was probably the easiest week yet. Lets see... We learned how to change bases:
1)rewrite problem in exponential form
2)take the log of both sides
3)move the variable to the front
4)solve
Eg. log5of10=x
5^x=10
log5x=log10
xlog5=1
x=1/log5
We also learned to graph exponential functions (ab^x):
if b is greater than 1, the graph goes up whereas if it is less than one, the graph goes down
Eg. f(x)=5(3)^x the graph would go up because b is greater than one
The formulas are pretty ease but remembering them will be pretty hard and using them in the correct problem will also be kinda hard.
A(t)=Ao(1+r)^t
Ao = what you start with
r = rate
t = time
A(t)=Aob^t/k
Ao = what you start with
t = time
b = double, half, etc.
k = regular time to double, half, etc.
Eg. half-life of 5 days
b = ½
k = 5
A(t)=Ao(1/2)^t/5
P(t)=Poe^rt
Po = wha tyou start with
r = rate
t = time
you only use the problem with p when it says compounding continuously in the problem
then theres the limit thing and rule of 72 (72 / r% = how long it takes to double)
As for the test on Friday, I didnt completely get it because of the fact that it was a quiz... and, like many others, I completely forgot everything once I saw it.
For the test tomorrow, I'm probably not ready but I'm trying to study as much as I can before then and if anyone could help with remembering the formulas if anyone has any tricks or anything, I'd appreciate help.
Sunday, September 27, 2009
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haha yeah well, I'm not too good with making up tricks for remembering things according to D.W. because I just make up songs to remember things and he thinks that's stupid. You can try that if you would like but it's fine if you don't want to.
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