[Math Revolution GMAT math practice question]
If x^2=x+1, then x^4=?
A. 3x+2
B. 3x-2
C. 2x+3
D. 2x-3
E. 3x+4
If x^2=x+1, then x^4=?
This topic has expert replies
- Max@Math Revolution
- Elite Legendary Member
- Posts: 3991
- Joined: Fri Jul 24, 2015 2:28 am
- Location: Las Vegas, USA
- Thanked: 19 times
- Followed by:37 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
Math Revolution
The World's Most "Complete" GMAT Math Course!
Score an excellent Q49-51 just like 70% of our students.
[Free] Full on-demand course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions.
[Course] Starting $79 for on-demand and $60 for tutoring per hour and $390 only for Live Online.
Email to : [email protected]
- GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Squaring both sides, we get:Max@Math Revolution wrote:[Math Revolution GMAT math practice question]
If x^2=x+1, then x^4=?
A. 3x+2
B. 3x-2
C. 2x+3
D. 2x-3
E. 3x+4
(x²)² + (x+1)²
x� = x² + 2x + 1
Substituting x²=x+1 into x� = x² + 2x + 1, we get:
x� = (x+1) + 2x + 1
x� = 3x + 2
The correct answer is A.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
- fskilnik@GMATH
- GMAT Instructor
- Posts: 1449
- Joined: Sat Oct 09, 2010 2:16 pm
- Thanked: 59 times
- Followed by:33 members
\[?\,\,\,:\,\,\,{x^4}\,\, = \,\,{\left( {{x^2}} \right)^2}\,\,\mathop = \limits^{\left( * \right)} \,\,{\left( {x + 1} \right)^2}\,\, = \,\,{x^2} + 2x + 1\,\,\mathop = \limits^{\left( * \right)} \,\,x + 1 + 2x + 1\]Max@Math Revolution wrote:[Math Revolution GMAT math practice question]
If x^2=x+1, then x^4=?
A. 3x+2
B. 3x-2
C. 2x+3
D. 2x-3
E. 3x+4
\[?\,\, = \,\,3x + 2\]
This solution follows the notations and rationale taught in the GMATH method.
Regards,
Fabio.
Fabio Skilnik :: GMATH method creator ( Math for the GMAT)
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
English-speakers :: https://www.gmath.net
Portuguese-speakers :: https://www.gmath.com.br
- Max@Math Revolution
- Elite Legendary Member
- Posts: 3991
- Joined: Fri Jul 24, 2015 2:28 am
- Location: Las Vegas, USA
- Thanked: 19 times
- Followed by:37 members
=>
x^4 = (x^2)^2 = (x+1)^2 = x^2 + 2x + 1 = (x + 1) + 2x + 1 = 3x + 2.
Therefore, the answer is A.
Answer: A
x^4 = (x^2)^2 = (x+1)^2 = x^2 + 2x + 1 = (x + 1) + 2x + 1 = 3x + 2.
Therefore, the answer is A.
Answer: A
Math Revolution
The World's Most "Complete" GMAT Math Course!
Score an excellent Q49-51 just like 70% of our students.
[Free] Full on-demand course (7 days) - 100 hours of video lessons, 490 lesson topics, and 2,000 questions.
[Course] Starting $79 for on-demand and $60 for tutoring per hour and $390 only for Live Online.
Email to : [email protected]