In the first series, the summation applies to the whole (2n+3) inside
the parentheses, so the 3 gets summed up 5 times.
But in the second one, the summation only applies to the 2n , so
the 3 is only added after the summation is finished.
The difference between five 3s the first time and one 3 the second time
is your 12 .
Answer:
b)-9,2
Step-by-step explanation:
x^2+7x-18=0
x^2+9x-2x-18=0
x(x+9)-2(x+9)=0
(x+9)(x-2)=0
therefore
x=-9
x=2
Answer:
Learn how to find explicit formulas for arithmetic sequences. For example, find an explicit formula for 3, 5, 7,... ... CCSS Math: HSF. ... plug in the number of the term we are interested in, and we will get the value of that term. ... Writing explicit formulas ... Check out, for example, the following calculations of the first few terms.
Step-by-step explanation:...
Answer:
The volume of a right circular cone is 
.
Step-by-step explanation:
The circumference of the base of a right circular cone is 125.6 ft.
Height of cone is 75 ft.
Circumference of base is :
, r is radius
The volume of a cone is given by :
So, the volume of a right circular cone is .
