UrbanPro
true

Take Class 12 Tuition from the Best Tutors

  • Affordable fees
  • 1-1 or Group class
  • Flexible Timings
  • Verified Tutors

Search in

x(1-f) Equals: A) 1, B) Less Than, 1 C) More Than 1, D) Between 1 And 2

Sujoy Das
07/02/2018 0 0

Question:

If x = (9 + 4rt(5))^48 = [x] + f, where [x] is integral part of x and f is a fraction, then x(1-f) equals:

a) 1 b) less than 1 c) more than 1 d) between 1 and 2.

Answer:

Method:

Take y = (9 - 4rt(5))^48 ; 0 < y < 1

=> xy = 1 and x+y = Integer

x + y = [x] + 1

[x] + f + y = [x] + 1

y = 1 - f

So x(1-f) = xy = 1

0 < y < 1

And x + y = Integer

When you add x + y,  integer that would come would be [x] + 1.

 

0 Dislike
Follow 4

Please Enter a comment

Submit

Other Lessons for You

Best shortcuts to use in mathematics problems.
Many students ask me question "is there any shortcut methods to solve a question?" actually I want to refer to the answer of this question. First of all, shortcuts is not acceptable by your board exams....

Vishal Pandey

1 0
0

Maths Done Right.
Maximum students waste those crucial few seconds calculating simple multiplication. Few tricks that might help saving 10-15mins..Remember, saving 10 mins is like gold in board examination. 1. Multiplying...

Cross product of vectors
Vector or Cross product of vectors It is defined as product of magnitude of the vectors and sine of the angle between them it is a vector quantity. For two vectors A and B A × B = |A||B| SinTn...

Straight Lines Important Chapter 3 In Class 11th Students Only
Online video lectures only for studetns https://www.youtube.com/watch?v=LTdgK_PnTX0&t=132s

Understanding Limits Through Graphs
Maths is often taught mechanically. Just consider the case of limits. Most of the standard textbooks define, the limit is the value that a function "approaches" as the input "approaches" some value. This...
A

Abhilash K S

1 0
0
X

Looking for Class 12 Tuition Classes?

The best tutors for Class 12 Tuition Classes are on UrbanPro

  • Select the best Tutor
  • Book & Attend a Free Demo
  • Pay and start Learning

Take Class 12 Tuition with the Best Tutors

The best Tutors for Class 12 Tuition Classes are on UrbanPro

This website uses cookies

We use cookies to improve user experience. Choose what cookies you allow us to use. You can read more about our Cookie Policy in our Privacy Policy

Accept All
Decline All

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 55 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 7.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more