Answer:
$9327
Step-by-step explanation:
Apparently, the cost function is supposed to be ...
C(x) = 0.4x^2 -112x +17167
This can be rewritten to vertex form as ...
C(x) = 0.4(x^2 -280) +17167
C(x) = 0.4(x -140)^2 +17167 -0.4(19600)
C(x) = 0.4(x -140)^2 +9327
The vertex of the cost function is ...
(x, C(x)) = (140, 9327)
The minimum unit cost is $9327.
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<em>Comment on the question</em>
You found the number of units that result in minimum cost (140 units), but you have to evaluate C(140) to find the minimum unit cost.
Answer:
k=10
Step-by-step explanation:
g(x)=2x^2+ kx+18
when x=-2
g(-2)=2 (-2)^2 -2k +18
Since when x is -2, y =6
6=2 (-2)^2 -2k +18
6=18+8-2k
2k=26-6
2k=20
k=10
This revolves around exact trig values - no easy way to say this, you just need to memorise them. They are there for sin cos and tan, but I will give you the main tan ones below - note this is RADIANS (always work in them when you can, everything is better):
tan0: 0
tanpi/6: 1/sqrt(3)
tanpi/4: 1
tanpi/3: sqrt(3)
tanpi/2: undefined
Now we just need to equate -2pi/3 to something we understand. 2pi/3 is 1/3 of the way round a circle, so -2pi/3 is 1/3 of the way round the circle going backwards (anticlockwise), so on a diagram we already know it's in the third quadrant of the circle (somewhere between pi and 3pi/2 rads).
We also know it is pi/3 away from pi, so we are looking at sqrt(3) or -sqrt(3) because of those exact values.
Now we just need to work out if it's positive or negative. You can look up a graph of tan and it'll show that the graph intercepts y at (0,0) and has a period of pi rads. Therefore between pi and 3pi/2 rads, the values of tan are positive. Therefore, this gives us our answer of sqrt(3).
Answer:
If he scored x points in the first half, then x + p = 31
