Completing the Square: Tips for Solving Equations with Coefficients

  • Thread starter Thread starter musicfairy
  • Start date Start date
  • Tags Tags
    Square
Click For Summary
SUMMARY

The discussion focuses on the method of completing the square for quadratic equations that include a leading coefficient. The key technique involves factoring out the leading coefficient from all terms before applying the completing the square formula, specifically using the identity (x-a)² = x² + 2ax + a². An example provided illustrates this process with the equation 4(y² − y + 1/4) − 3, leading to the final form 4(y − 1/2)² − 4.

PREREQUISITES
  • Understanding of quadratic equations and their standard form.
  • Familiarity with the concept of completing the square.
  • Basic algebraic manipulation skills, including factoring.
  • Knowledge of the identity (x-a)² = x² + 2ax + a².
NEXT STEPS
  • Practice completing the square with various leading coefficients.
  • Explore the derivation of the quadratic formula from completing the square.
  • Learn about the applications of completing the square in solving real-world problems.
  • Investigate the relationship between completing the square and graphing quadratic functions.
USEFUL FOR

Students studying algebra, mathematics educators teaching quadratic equations, and anyone looking to enhance their problem-solving skills in algebraic contexts.

musicfairy
Messages
101
Reaction score
0
cs.jpg


So far all the completing the square problems I've done do not have a coefficient in front of the highest power. This one has me stuck. :( What should I do to complete the square?
 
Physics news on Phys.org
Factor the leading coefficient out of all the terms and then complete the square.
 
(x-a)2= x2+ 2ax+ a2. After you have factored out that leading 4, what is "a"?
 
So would it be something like this?

4(y2 − y +1/4) − 3 − 1
4(y− 1/2)2 − 4
 
Last edited:
It would be a lot like that.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

Similar threads

  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 29 ·
Replies
29
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
4
Views
2K
Replies
3
Views
2K
  • · Replies 25 ·
Replies
25
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K