Home
Class 12
MATHS
If (8 + 3sqrt(7))^(n) = P + F , where P...

If `(8 + 3sqrt(7))^(n) = P + F ` , where P is an integer and F is a proper fraction , then

A

P is a odd integer

B

P is an even integer

C

`F(P + F) = 1`

D

`(1 - F ) (P + F) = 1`

Text Solution

Verified by Experts

The correct Answer is:
a,d

We have , ` (8+ 3 sqrt(7))^(n) = (8 + sqrt(63))^(n)`
Now ,let ` P + F = (8 + sqrt(63))^(n)` …(i)
` 0 lt F lt 1` ….(ii)
and let ` F' = (8 - sqrt(63))^(n)` ….(iii)
` 0 lt F' lt 1 ` …(iv)
On adding Eqs (i) and (iii) , we grt
` P + F + F' = (8 + (sqrt(63))^(n) + (8 - sqrt(63))^(n)` ...(v)
` rArr P + 1 = 2p ` (even integer ) , ` AA p in ` N
` rArr P= 2p - 1 ` = odd integer
` therefore F' = 1 - F `
` therefore (1 - F ) (P - F ) = F' (P + F) = (8 - sqrt(63))^(n) (8 + sqrt(63))^(n)`
` = (64 - 63 )^(n) = 1^(n) = 1 `
Promotional Banner

Topper's Solved these Questions

  • BIONOMIAL THEOREM

    ARIHANT MATHS|Exercise Exercise (Passage Based Questions)|21 Videos
  • BIONOMIAL THEOREM

    ARIHANT MATHS|Exercise Exercise (Single Integer Answer Type Questions)|9 Videos
  • BIONOMIAL THEOREM

    ARIHANT MATHS|Exercise Exercise (Single Option Correct Type Questions)|30 Videos
  • AREA OF BOUNDED REGIONS

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|23 Videos
  • CIRCLE

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|16 Videos

Similar Questions

Explore conceptually related problems

If (3sqrt(3)+5)^(7)=P+F where P is an integer and F is a proper fraction,then F(P+F)=

If (3sqrt(3)+5)^(n)=p+f. where p is an integer and f is a proper fraction.then find the value of (3sqrt(3)-5)^(n),n in,N, is

If (9 + 4 sqrt(5))^(n) = I + f ,n and l being positive integers and f is a proper fraction , show that (I-1 ) f + f^(2) is an even integer.

If (7 + 4 sqrt(3))^(n) + 5 + t , where n and s are positive integers and t is a proper fraction , show that (1 - t) (s + t) = 1

Let R=(5sqrt(5)+11)^(31)=1+f, where I is an integer and f is the fractional part of R then Rf is equal to

if (7+4sqrt(3))^(n)=p+beta where n&p are positive integers and beta is a proper fraction show that (1-beta)(p+beta)=1

If n is a positive integer and (3sqrt(3)+5)^(2n+1)=l+f where l is an integer annd 0 lt f lt 1 , then