SOLUTION: Please help me solve f(x)= -2(3)^x +1 and how do u graph this? Thanks

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Question 598044: Please help me solve f(x)= -2(3)^x +1 and how do u graph this? Thanks
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)= -2(3)^x +1
:
-2%283%5Ex%29%2B1 = 0
-2%283%5Ex%29 = -1
divide both sides by -2
3%5Ex = %28-1%29%2F%28-2%29
:
3%5Ex = .5
using nat logs
x*ln(3) = ln(.5)
x = ln%28.5%29%2Fln%283%29
x = -.631
:
To graph this make a table of values starting with x=-2, the every half unit to x=+2
Using a calc:
y = -2(3^-2) + 1
y = -2(.111) + 1
y = .777
Find y for each value of x,
x | y
-------
-2.0|.78
-1.5|.62
-1.0|.33
-0.5|-.15
0.0 |-1.0
+0.5|-2.5
+1.0|-5
+1.5|-9.4
+2.0|-17
Your graph should look alot like this
graph%28+300%2C+200%2C+-2%2C+5%2C+-20%2C+4%2C+-2%283%5Ex%29%2B1%29+