All Answers 358087 Answers

Very nice, Erlich  and Guest.........!!!

Thank you so much for your help, I feel that I am getting it. Thank you again.

Thank you, that's what I got last time but it says it was wrong.

True, what you say! The more patterns you see and can explain clearly and coherently the better!.

However, in this sequence, I see a VERY CLEAR pattern, which is very familiar to me!

The sequence is: 1, 2, 3, 8, 15, 48, 105, 384, 945, 3840, 10,395, 46,080......etc.
This is the double factorial function of all positive integer 1, 2, 3 4,.....etc. It is a generalization of the usual factorial n! defined by n!!. For odd n {n·(n - 2)...5·3·1, the product is odd.  For even n·(n - 2)...6·4·2, the product is even.  Note that -1!! = 0!! = 1, by definition. 

                           Algebra                Not in Algebra         Total

Chemistry               6                          6                          12

Not in Chemistry    11                        17                         28

Total                       17                        23                         40

Part A   

N(Algebra or Chemistry)  = N(Algebra) + N(Chemistry)  - N(Algebra and Chenistry)  =

                                                17          +     12                                    6                     =     23

Part B  

Just chemistry  =  (6/40)*2000  =   300

bpooop

Part A  with replacement  =   4/52 * 4/52  =  16/ 2804   =  1 / 169

Part B without replacement  =  13/52  * 13/51   you are correct   FWAS....!!!....just do the math, now!!!

The second is dependent......the probability of drawing a spade on the second draw might be either 13/51 or 12/51    depending on what card is drawn first...... 

I think i got the answer.

The sequence can be described by the following formula: a_n+2=a_n*(n+2), a₁=1 and a₂=2

That means the next 3 terms are: 384*10=3840, 945*11=10395, 3840*12=46080

But there is something else i want to add about this type of questions:

I feel its a little bit silly, because you could always find another pattern or another way. Of course, if you need to answer that type of questions in a test, you cant write that, you'll have to do what they expect you to do. But i feel its wrong NOT to mention what im going to.

I once heard a joke about a mathematician that has an interesting way of answering those questions: he simply writes "19" when he's asked to find the next term. He justifies that with one of the theorems of a famous mathematician called Lagrange. And in my opinion he's right. Saying that there is a finite amount of answers is silly, because there isnt. There is always a way to make order out of what seems to be chaos.

I dont know if you love math or care about it, but if you do, remember it.

Let H  = P(Honor roll)  =.30

Let J = P(Part-time Job)  = .70

P ( H and J)  =   .25

We want to find

P (H l J )   =    P(H and J)  / P(J)   =     .25  /  .70    =   .357   ≈   36 %

P( 41-55  or Disney World)  = P(41-55)  + P(Disney World)  - P(41-55 and Disney World)

P( 41-55  or Disney World)  =   .36         +       .42                  -         .11    

 =    .67   =  67%

We could draw the 3 first and then the 7.....or we could draw the 7 first and then the 3....so...

P(drawing the first card) =  4/52  .....P(drawing the second card)  = 4/51

And we can do this in 2 ways  "7" first and then "3"  or vice-versa

2 (4/52) (4/51)   = 2(1/13)(4/51)  =  8/663

These are definitely dependent events

Notice asinus, that  for  (4,5) , y =  -x + 9    is correct

But....for   (-2, - 7)    we have that   f(-2)  =  - (-2) + 9   =  11    which is incorrect

the multiples of i 

i^9  i^100  i^2017

how to answer these questions

\(i=\sqrt{-1}\)

i^1=  i

i^2=-1

i^3= -i

i^4= 1

i^5=  i

\(i^9 =(i^3)^3=(-i)(-i)(-i)=(-1)(-i)=i\)

\(i^{100}=((i^5)^5)^4=(i^5)^4=i^4=1\)

\(i^{2017}=(i)(i^{2016})\)  ?

Excuse me. Unfortunately I do not know.

  !

Let B  = Probability of buying a car and being male    21/88

Let M = Probability of being a male  =  48/88 

P(B l M)   =  P(B and M) / P(M)   =   (21/88) / (48/88)  = 21/48  = .4375  = 44%

suatu fungsi dengan rumus f(x)=ax+b jika f(4)=5 dan f(-2)= -7 , maka tentuka rumus fungsi f(x)?

A function f(x) = ax + b.    If  f(4) = 5 and  f(-2) = -7, then the function is f(x) = ?

\( f (x) = ax + b\)

\( f (4) = a\cdot 4 + b=5\)

\(a=\frac{5-b}{4}\)

\( f (-2) = -2\cdot a + b=-7\)

\(a=\frac{-7-b}{-2}\)

\(\frac{-7-b}{-2}=\frac{5-b}{4}\)

\(-28-4b=2b-10\)

\(6b=-18\\\color{blue}b=-3\)

\(a=\frac{5-b}{4}\\a=\frac{5+3}{4}\)

\(a=2\)

\(\large f(x)=2x-3\)

  ! Thank you C.

Thank you, so what makes them not independent?

Thank you, that's what I came up with but it said I was incorrect. Maybe it's D?

Translation......we wish to write the equation of a line in the form y = mx + b given the points (4, 5)  and (-2, -7)

First.....find the slope  =   [subtract y's in some order] / [ subtract x's in the same order]

So we have

[ -7 - 5] / [ -2 - 4]  =  -12/ -6    = 2

And using either point ....the point-slope form becomes

y = 2(x - 4) + 5  simplify

y = 2x - 8  + 5

y = 2x  - 3

Actually I have thanked both many times so maybe you shouldn't assume things just like you assumed my gender. I'm actually learning thanks to Chris's explanations.

none of your business

thats sooo long!

i know right!

that is such a confusing Q!!! im only in yr7!!!

\(z=x{e}^{-y/x} , x({d}^{2}z/dxdy)+2(dz/dx+dz/dy)=y({d}^{2}z/d{y}^{2}) \) это уравнение,Проверить удовлетворяет ли функция з=з(х;Г) дифференциальному уравнению.Как это сделать?d-это дифференц,в моем уравнении он обозначен 6 только наоборот.