Sequences functions

[honest coral]

g(n) = 5(2)^n-1
g(3) =
idk what i am doing wrong but i get 0.625 which is wrong apparently

[crude current]

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[broken mountain]

$g(n) = 5(2)^{n-1}$

[digital oasis]

wolfqz

[broken mountain]

is that correct?

[honest coral]

yeah

[broken mountain]

so to find g of any variable a, $g(a) = 5(2)^{a-1}$

[digital oasis]

wolfqz

[broken mountain]

do the same for 3

u get $g(3) = 5(2)^{3-1} = 5(2)^2 = 5(4) = 20$

[digital oasis]

wolfqz

[honest coral]

ok but what if g(-2)

[broken mountain]

just put -2 instead of n

[honest coral]

-2-1 = -3

2^-3 = 0.125

[broken mountain]

oh $x^{-n} = \frac{1}{x^n}$

[digital oasis]

wolfqz

[broken mountain]

$g(-2) = 5(2)^{-2-1} = 5(2)^{-3} = 5\left(\frac{1}{2^3}\right) = \frac{5}{8}$

[digital oasis]

wolfqz

[broken mountain]

its 0.625

[honest coral]

what my math techer says that incorrect......

[broken mountain]

for g(-2), 5/8 is incorrect?

[honest coral]

yeah idk why

[broken mountain]

uhh lets give it to a computer

,w 5(2)^(-2-1)

[digital oasis]

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Requested by wolfqz

[broken mountain]

yeah its 0.625

[honest coral]

err ok

+close