I NEED HELP QUICK !! a1=8 ai=ai-1 *(-1.5) find sum of the first 20 terms in this geometric sequence

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

just took the test and my answers down below!

step-by-step explanation:

check the pic :

correct answer was 0.5

all of the measures need to be converted to the same measure; such as inches. if you do that it is easy to determine which is the longest, 2500 mm which is approximately 97.5 inches.