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:
9x+6
Step-by-step explanation:
(3x+2)+2(3x+2)
3x+2+6x+4
9x+6
I hope this helps you
9.8.7!-7!
7! (72-1)
7!.71
Answer:
+ 6°F
Step-by-step explanation:
Change is (Final - Initial) [Change is subtract old value from new value]
(0°F -(-6°F)) = +6°F
Step-by-step explanation:
Helo
your answer refer to the attachment
