Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Re: 4^x + 4 ^-x = 2 What is the value of X [#permalink]
07 Feb 2012, 09:50

2

This post received KUDOS

Expert's post

1

This post was BOOKMARKED

nimc2012 wrote:

4^x + 4 ^-x = 2. What is the value of x?

a) -1 b) -1/2 c) 0 d)1/2 e) 1

Thanks

Plug-in method should work form most of the people.

Else you can realize that \(4^x+\frac{1}{4^{x}}=2\) is the sum of a positive number and its reciprocal and it to equal to 2 each must be 1 --> \(4^x=1\) --> \(x=0\);

Re: 4^x + 4 ^-x = 2 What is the value of X [#permalink]
25 Jun 2013, 11:41

3

This post received KUDOS

4^x + 4^-x = 2 What is the value of x?

a) -1 b) -1/2 c) 0 d) 1/2 e) 1

Both X and -X are present in the equation as exponents. Hence if there is any solution to the equation, there would be another solution to the equation with the same absolute value and opposite polarity and so there cannot be a unique solution. So hypothetically if -1 is the answer then +1 would also be a solution and the same for -1/2 and +1/2. '0' is the only number without polarity. Hence answer is C

On September 6, 2015, I started my MBA journey at London Business School. I took some pictures on my way from the airport to school, and uploaded them on...

When I was growing up, I read a story about a piccolo player. A master orchestra conductor came to town and he decided to practice with the largest orchestra...

I’ll start off with a quote from another blog post I’ve written : “not all great communicators are great leaders, but all great leaders are great communicators.” Being...