The sum if the geometric sequence given by:
an=-2(3)^(n-1)
will be:
when:
n=1
an=-2
when n=2
a2=-6
when n=3
a3=-18
when n=4
a4=-54
when n=5
a5=-162
when n=6
a6=-486
when n=7
a7=-1458
when n=8
a8=-4374
thus the summation of the term will be:
Sn=(-4374+-1458+-486+-162+-54+-18+-6+-2)
Sn=-6560
the answer is -6560
Answer:
x = -1 and x = 4
Step-by-step explanation:
Firstly solve the quadratic expression of
2x^2-6x-8 = 0....it gives you the two brackets of.....(2x-8)(x+1)=0
then...you equate the two brackets to 0.separately
2x-8 = 0....which gives you...x = 4...as the first solution..then..;
x+1 = 0....which gives you...x = -1...as the second solution
Answer:
7.12 kilometers
Step-by-step explanation:
Add the amounts of kilometers to find the total :
3.8 kilometers + 3.32 kilometers = 7.12 kilometers
Answer:
Step-by-step explanation:
84 = 2 * 2 *3 * 7