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**RauLiTo**- Replies: 1

I have to answer these questions as an assignment ... Please guys try to help me as much as you can !

Thanks in advance !

9 ^ Abc

Welcome ... what do you think ?!

Hello bobbym ... I am using android lock as an application in the iPhone and I just discovered that its different from the original one in andoird ... first it can have from 3 to 10 digits and second I can use the digit more than one time in the same pattern.

my answer is 187209804 ... I used excel in solving it ... !

Any other thoughts ?!

Thanks for sharing that link bobbym ... any other thoughts ?

Is it very hard ?!

**RauLiTo**- Replies: 12

I miss this forum very much and I came back to it with one question ... Let's try !

1 2 3

4 5 6

7 8 9

The pictures above show Android lock screen ... you can lock your mobile by one patterns like the above contain 3 digits minimum and 10 maximum. How many different pattern can you make ?

Note: you can go cross i.e from 1 to 8 or from 6 to 7 ...

my answer is : 18******* !

any different answers ?

why there is no arabic !

**RauLiTo**- Replies: 18

find

the value of this infinite series

you can write it like this :

(1 ² - 2 ²) + (3 ² - 4 ² ) + ( 5 ² - 6 ²) + ... +199 ²

-3 + - 7 + - 11 + ...

its a series now

or you can do it with sigma like this :

thanks alot alot guys ...

i forgot to put the power ( 1 / 2 ) in one of them ...

i think this is the first step ... but maybe there are special way ... because it will take long time to do it with the natural way ...

who can countinue ?

**RauLiTo**- Replies: 6

differentiate this with respect to x

it seems boring ... help please

this way in my mind ... but i want to make sure ... so what is the answer ... help please

**RauLiTo**- Replies: 4

6 men want to marry from 6 women ... for each man there was a sister from the 6 women ... and we all know that the brother cant marry his sister ...

how many ways that can be with ?!

because by checking it with the calculator you will see that cos20cos40sin80 ≠ 1 / 8

very very nice !!!

thats the question

i know the rule for

sin / cos 3 θ but i dont know how to use it !

heheheh ooh

we want the sin 25 now or maybe there is a different way

oooh thanks alot luca .... anybody else ?

guys ?!