Represent the geometric series using the explicit formula.

12, −36, 108, −324, …

f(n) = f(n − 1) ⋅ (−3)
f(n) = f(n − 1) ⋅ (3)
f(n) = 12 ⋅ (−3)(n−1)
f(n) = 12 ⋅ (3)(n−1)

answer:

 f(n)=12(-3)^{(n-1)}

Step-by-step explanation:

The Explicit formula in function notation for a geometric series is:

Where  is the nth term of the sequence,  is the first term in the sequence and  is the common ratio.

Given the following geometric serie:

The common ratio is:

And the first term is:

Therefore, substituting values, we get that the Explicit formula that represents this geometric series is:

i wish i could u

step-by-step explanation:

i wish i could u

c.   x=2.4cm

step-by-step explanation:

similar triangles are triangles which have the same shape but not the same size. this means their angle measures are equal but their side lengths are not instead they are proportional. to solve, we will set up a proportion and solve.

a proportion is two equal ratios set equal to each other. we form the ratios by finding corresponding sides (sides which match to each other on both triangles by their position). out ratios will be one side of the small triangle over the corresponding side on the big triangle as shown below:

.

to solve the proportion, we'll cross multiply by multiplying numerator with denominator across the equal sign.