Question

Derivatives/Calculus
http://gyazo.com/1914cb3cba2ce52f28eb3cf71b2befff

Answer 1

total selling price is just x times p
you can understand why ?

Answer 2

then just Profit = selling price - cost price...

Answer 3

I don't understand why x*p is total selling price?

Answer 4

cost of selling 1 suit = p
cost of selling 'x' suit = xp
selling price = revenue function R(x)

Answer 5

so just -0.5x^2+180x?

Answer 6

yep

Answer 7

so then it's (0.5x^2+180x)-(4000-0.25x^2) for P(x)

Answer 8

-0.5x^2
(-0.5x^2+180x)-(4000+0.25x^2) for P(x)

Answer 9

So then x suits would be setting the deriv of P(x) to zero

Answer 10

whatever you get for 'x' after setting P'(x) = 0
will go in
\(\square \: suits\)

Answer 11

yes, you said correct

Answer 12

So I got 20.4, so it's 20 suits?

Answer 13

i am getting
x= 120 exactly

Answer 14

you did this, right ?
(-0.5x^2+180x)-(4000+0.25x^2) = P(x)
?

Answer 15

check for signs

Answer 16

Okay now I got 120 ;P Idk what I did wrong.
So maximum profit =180-0.5*120

Answer 17

no

Answer 18

no wait that's price.

Answer 19

yes

Answer 20

0.75x^2+180x-4000 input 120 for x

Answer 21

to get max profit
put x=120 in (-0.5x^2+180x)-(4000+0.25x^2) = P(x)

Answer 22

check for signs

Answer 23

got 6800 (sorry)

Answer 24

Then for PPU it'd be 56.67?

Answer 25

6800 correct
PPU = p only right ?

Answer 26

p = 180 -x/2 , isn't it ? = 180-60 =120

Answer 27

OOh right sorry I wasn't calculating in cost, only revenue

Answer 28

So that's it?:O

Answer 29

yes, you answered all questions there...

Answer 30

Looked a lot harder.

Answer 31

http://gyazo.com/1fc37f0420b2fa1f8af24020afa754c9
Last question:-)

Answer 32

So A. 0.006x^3+0.07x^2+18x+700 when x=25
B. (0.006(26)^3+0.07(26)^2+18(26)+700)-(0.006(25)^3+0.07(25)^2+18(25)+700)/26-25

Answer 33

C. C'(x) when x=25
D. C'(x) when x=27 - C'(x) when x=25
E. 0.006x^3+0.07x^2+18x+700 when x=27?

Answer 34

yeah, i think those are correct..
not sure about B though ....

Answer 35

Essentially it's just (0.006(26)^3+0.07(26)^2+18(26)+700)-(0.006(25)^3+0.07(25)^2+18(25)+700)

Answer 36

okk, if your are confident :)

Answer 37

The 26-25 idk, that's how I learned it. It'll always equal 1

Answer 38

Okay @hartnn if you were told "Round to the nearest cent" what would you put if your answer was 1353.1356

Answer 39

nearest cent means 2 decimal places
1353.14

Answer 40

Okay... I got it marked wrong and I put that, it said it was 1353.00 lol :(

Answer 41

lol, thats not rounded to nearest cent!

Answer 42

1353.14 must be correct, stupid software :P

Answer 43

Well im sure my teacher wants me to fail ;P