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

AI Generated Solution

The correct Answer is:
To solve the problem, we need to analyze the expression \((8 + 3\sqrt{7})^n\) and express it in the form \(P + F\), where \(P\) is an integer and \(F\) is a proper fraction. ### Step-by-Step Solution: 1. **Understanding the Expression**: We start with the expression: \[ (8 + 3\sqrt{7})^n = P + F \] where \(P\) is an integer and \(F\) is a proper fraction. 2. **Finding the Complement**: To find \(F\), we consider the conjugate of the expression: \[ (8 - 3\sqrt{7})^n \] This will help us find \(F\) because it will yield a similar structure but with a negative term. 3. **Adding the Two Expressions**: Now we add the two expressions: \[ (8 + 3\sqrt{7})^n + (8 - 3\sqrt{7})^n = P + F + P' + F' \] Here, \(P'\) and \(F'\) are the integer and fractional parts of \((8 - 3\sqrt{7})^n\). 4. **Simplifying the Sum**: The sum simplifies to: \[ (8 + 3\sqrt{7})^n + (8 - 3\sqrt{7})^n = 2P \] since the irrational parts (the terms involving \(\sqrt{7}\)) will cancel out. 5. **Identifying the Fractional Parts**: The fractional parts \(F\) and \(F'\) will also sum up: \[ F + F' = 1 \] because both \(F\) and \(F'\) are proper fractions. 6. **Conclusion about \(P\)**: Since \(2P\) is an integer, \(P\) must also be an integer. However, since \(F + F' = 1\) and both are proper fractions, it follows that: - \(F\) and \(F'\) are both in the range \(0 < F, F' < 1\). - Therefore, \(P\) must be odd (since \(P + 1\) is even). ### Final Result: Thus, we conclude that \(P\) is an odd integer.

To solve the problem, we need to analyze the expression \((8 + 3\sqrt{7})^n\) and express it in the form \(P + F\), where \(P\) is an integer and \(F\) is a proper fraction. ### Step-by-Step Solution: 1. **Understanding the Expression**: We start with the expression: \[ (8 + 3\sqrt{7})^n = P + F ...
Promotional Banner

Topper's Solved these Questions

  • BIONOMIAL THEOREM

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

    ARIHANT MATHS ENGLISH|Exercise Binomial Theorem Exerciese 4 : Single Integer Answer Type Questions|1 Videos
  • BIONOMIAL THEOREM

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

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

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

Similar Questions

Explore conceptually related problems

If (3sqrt3 + 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 (3sqrt3-5)^n,nin,N, is

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

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

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

If (9+4sqrt(5))^(n)=p+beta , where n and p are positive integers and beta is a positive proper fraction, prrove that (1-beta)(p+beta)=1 and p is an odd integer.

If (4+sqrt(15))^n=I+f, where n is an odd natural number, I is an integer and ,then a. I is an odd integer b. I is an even integer c. (I+f)(1-f)=1 d. 1-f=(4-sqrt(15))^n

If f(x) = n , where n is an integer such that n le x lt n +1 , the range of f(x) is

If R = (7 + 4 sqrt(3))^(2n) = 1 + f , where I in N and 0 lt f lt 1 , then R (1 - f) equals

If in a positive integer such that If a number a=p+f whre p is an integer and 0ltflt1 . Here p is called the integral part of a and f its fractional part. Let n in N and (sqrt(3)+1)^(2n)=p+f , where p is the integral part and 0ltflt1 . On the basis of bove informationi answer teh following question: f^2+(p-1)f+4^n= (A) p (B) -p (C) 2p (D) -2p