Flag Algebra> value find...
question mark

2 to the power 405 divided by 7 then what is the quotient and remainder

first u have to find 2 to the power 405=? find the value

keshav kr , 14 Years ago
Grade 12
anser 3 Answers
Swapnil Saxena

If u need to find the remainder the remainder , theres no need to evaluate 2^405 , this can be solved in the following ways.

2405 = (8)135=(7+1)135

Binomially expand the above expression as

= 135C07135+135C17134+135C27133+...+135C13471+135C13570

= In the above expansion, all the terms are divisible by 7 (They consist of 7 as a factor)

= Only 135C135 70 = 1 is non divisible as such 1 is the remainder

If you wanna find the quotient  try logarithm

2405= antilog(405 log2) , it will give u a fair approx. values

Quotient = antilog(405*log2 - log7 )

Last Activity: 14 Years ago
Sathya

The remainder is 1....................

Last Activity: 14 Years ago
Sathya

2^405 mod 7

 

(2^5)^81 ?mod7

 

(4)^81 mod7

 

(4^3)^27 mod7

 

(1)^27 mod 7

 

1 mod7

 

Therefore remainder is 1............

Last Activity: 14 Years ago
star
LIVE ONLINE CLASSES

Prepraring for the competition made easy just by live online class.

tv

Full Live Access

material

Study Material

removal

Live Doubts Solving

assignment

Daily Class Assignments