How Did the Author Derive the Perfect Square from the Algebraic Equation?

Click For Summary

Homework Help Overview

The discussion revolves around the algebraic expression $$ 4a^4 + 8 a^3 + 8 a^2 + 4a + 1 $$ and its equivalence to the perfect square $$ ( 2a (a+1) + 1 )^2 $$. Participants are attempting to understand the derivation of this identity.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are exploring methods to manipulate the left-hand side (LHS) to match the right-hand side (RHS). Questions include how to factor the LHS and whether rewriting terms could help in recognizing a perfect square.

Discussion Status

There are various approaches being discussed, including factoring the LHS and rewriting terms to identify a perfect square. Some participants have suggested specific algebraic manipulations, but no consensus has been reached on a definitive method.

Contextual Notes

Participants have noted the absence of a formal homework statement or relevant equations, which may impact the clarity of the problem context.

MiddleEast
Messages
23
Reaction score
5
Homework Statement
NA
Relevant Equations
NA
Hello,
While following problem solution found this $$ 4a^4 + 8 a^3 + 8 a^2 + 4a + 1 = ( 2a (a+1) + 1 )^2 $$
Trying to figure out how did author do it but failed.
Anyone?
 
Physics news on Phys.org
MiddleEast said:
Homework Statement: NA
Relevant Equations: NA

Hello,
While following problem solution found this $$ 4a^4 + 8 a^3 + 8 a^2 + 4a + 1 = ( 2a (a+1) + 1 )^2 $$
Trying to figure out how did author do it but failed.
Anyone?
Well, what happens when you multiply out the RHS? Can you show those steps to see how close you get to the LHS?
 
Thanks for quick reply. It is simple to start with R.H.S to L.H.S.
As per solution, they move from L.H.S to R.H.S, thats my question how to play with it?
Tried to get different common factors over and over, no success. It is supposed to move from L.H.S to R.H.S.
 
Just factor the LHS then. Do it in a first step to get <something> squared, and then look to simplify what is inside the squaring parenthesis...
 
MiddleEast said:
Homework Statement: NA
Relevant Equations: NA

Hello,
While following problem solution found this $$ 4a^4 + 8 a^3 + 8 a^2 + 4a + 1 = ( 2a (a+1) + 1 )^2 $$
Trying to figure out how did author do it but failed.
Anyone?
Try rewriting ##8a^2## as ##4a^2+4a^2##. I'm not sure what would motivate that other than trying to write the first three terms as a perfect square.
 
  • Like
Likes   Reactions: SammyS and MiddleEast
MiddleEast said:
Homework Statement: NA
Relevant Equations: NA

Hello,
While following problem solution found this $$ 4a^4 + 8 a^3 + 8 a^2 + 4a + 1 = ( 2a (a+1) + 1 )^2 $$
Trying to figure out how did author do it but failed.
Anyone?
If the RHS is a perfect square, then it must be of the form ##(\alpha a^2 + \beta a +1)^2##.

Now, solve for ##\alpha, \beta##.
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 14 ·
Replies
14
Views
3K
Replies
6
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
23
Views
5K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K