Answer:11.7
Step-by-step explanation:
I understand that it means that out of every 10 hours, a cat spends 7 sleeping (not 7 hours in a day).
this means that a cat is sleeping
a percentage stays constant, this means that a cat sleeps 70 % of each 10 hours, but also 70% of the day.
Function 1:
f(x) = -x² + 8(x-15)f(x) = -x² <span>+ 8x - 120
Function 2:
</span>f(x) = -x² + 4x+1
Taking derivative will find the highest point of the parabola, since the slope of the parabola at its maximum is 0, and the derivative will allow us to find that.
Function 1 derivative: -2x + 8 ⇒ -2x + 8 = 0 ⇒ - 2x = -8 ⇒ x = -8/-2 = 4
Function 2 derivative: -2x+4 ⇒ -2x + 4 = 0 ⇒ -2x = -4 ⇒ x = -4/-2 ⇒ x= 2
Function 1: f(x) = -x² <span>+ 8x - 120 ; x = 4
f(4) = -4</span>² + 8(4) - 120 = 16 + 32 - 120 = -72
<span>
Function 2: </span>f(x) = -x²<span> + 4x+1 ; x = 2
</span>f(2) = -2² + 4(2) + 1 = 4 + 8 + 1 = 13
Function 2 has the larger maximum.
an =a1+d(n-1)
where d is the common difference
d=5-8
d=-3
a1=8
an =8-3(n-1)
Choice C
