It is asking you to find the sum of k^2 - 1 from k=1 to k=4. Since that is only 4 numbers, calculating the sum by hand wouldn’t be that bad.
(1^2 - 1) + (2^2 - 1) + (3^2 - 1) + (4^2 - 1) = 26
The easier way to find the sum is to use a few simple formulas.
When we have a term that is just a constant c, the formula is c*n.
When we have a variable k, the formula is k*n*(n+1)/2.
When we have a squared variable, the formula is k*n*(n+1)*(2n+1)/6.
In this case, we have a squared variable k^2 and a constant of -1.
So plug in n=4 to the formulas:
4*5*9/6 - 1*4 = 26
The answer is 26
Answer:
D. 12.3 ft
Step-by-step explanation:
This problem requires the use of trigonometric ratios. This one specifically uses the cosine ratio as it provides the hypotenuse and is asking for the side that is adjacent to the angle.
cos(40°)=a/16
cos(40°)×16=a/16×16
cos(40°)×16=a
a=12.256 ft
The length of side a is D. 12.3 ft.
Area of a circle = πr²
Radius = 18/2 = 9
A = (3.14)(9)²
A = 254.34
Hope this helps :)
Answer:
:)
Step-by-step explanation:
y=6x-3
y=-3
-3=6x-3
-3=6x-3
+3 +3
=6x
Answer:
6
Step-by-step explanation:
