# Thread: Sequences Discrete Math

1. ## Sequences Discrete Math Answer requires justification, how would you do this?

2. ## Re: Sequences Discrete Math Originally Posted by inayat  Answer requires justification, how would you do this?
You just post a list of questions and wait to be handed the answers.
Well we want to be a help site. Therefore, we need to see work to know how to help.

Here is f) $4^8-3^8$ Now you write a reply explaining that answer.

3. ## Re: Sequences Discrete Math Originally Posted by Plato You just post a list of questions and wait to be handed the answers.
Well we want to be a help site. Therefore, we need to see work to know how to help.

Here is f) $4^8-3^8$ Now you write a reply explaining that answer.
For part f), i got told number of sequences containing no A = 3^8

Therefore 4^8-3^8 sequences contain at least one A

Is this correct?

4. ## Re: Sequences Discrete Math Originally Posted by inayat For part f), i got told number of sequences containing no A = 3^8

Therefore 4^8-3^8 sequences contain at least one A

Is this correct?
Correct! Now what about the others.

5. ## Re: Sequences Discrete Math Originally Posted by Plato Correct! Now what about the others.
For (a) i got 4^8 because i did number of sequences = 4 * 4* .... *4

(b) 4^6

(c) 4^7

(d) 4^5

(e) 4^6 + 4^7

Please correct me where i'm wrong if i am

6. ## Re: Sequences Discrete Math Originally Posted by inayat For (a) i got 4^8 because i did number of sequences = 4 * 4* .... *4

(b) 4^6

(c) 4^7

(d) 4^5

(e) 4^6 + 4^7 $\color{red}{\times}$

Please correct me where i'm wrong if i am
$\#(AB\text{ OR }D)=\#(AB)+\#(D)-\#(AB\text{ AND }D )$

7. ## Re: Sequences Discrete Math Originally Posted by Plato $\#(AB\text{ OR }D)=\#(AB)+\#(D)-\#(AB\text{ AND }D )$
Sorry so would it be 4^6 + 4^7 - 4^5 ?

8. ## Re: Sequences Discrete Math Originally Posted by inayat Sorry so would it be $4^6 + 4^7 - 4^5\large\color{blue}{\text{YES}}$ ?
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9. ## Re: Sequences Discrete Math Originally Posted by Plato .....
Thanks, do i need to work that solution out on a calculator or can i leave my final answer as that?

10. ## Re: Sequences Discrete Math Originally Posted by inayat Sorry so would it be 4^6 + 4^7 - 4^5 ? Originally Posted by Plato 