The problem can be solved step by step, if we know certain basic rules of summation. Following rules assume summation limits are identical.




Armed with the above rules, we can split up the summation into simple terms:





=> (a)
f(x)=28n-n^2=> f'(x)=28-2n
=> at f'(x)=0 => x=14
Since f''(x)=-2 <0 therefore f(14) is a maximum
(b)
f(x) is a maximum when n=14
(c)
the maximum value of f(x) is f(14)=196
Answer:
$6.21
Step-by-step explanation:
1 apple = $0.60
3 apples = $1.80 (Multiply 0.60 by 3)
2 bananas = $1.00 (Multiply 0.50 by 2)
1 quart of yoghurt = $4.50
Add the prices up first:
1.80 + 1.00 + 4.50 = $7.30
7.30 off 15% = $6.21
Answer:
481
Step-by-step explanation:
Lets say width = x
Length = x+24
Perimeter is 100 so
100=x+24+x+24+x+x
100=4x+48
100-48=4x
52=4x
x=13
So width = 13
Length = 37
37x13=481
Answer:
C: 6
Step-by-step explanation:
Let's work backward. If that ? is replaced by 6, we have:
x^2 + 12x + 36 = (x + 6)^2.
The coefficient in question is 6.