Why is x2 . y2 not equal to (x-y) (x+y)?

  • Context: High School 
  • Thread starter Thread starter Atqiya
  • Start date Start date
  • Tags Tags
    Algebra Operations
Click For Summary
SUMMARY

The equation x² · y² is not equal to (x - y)(x + y). The correct identity is x² - y² = (x - y)(x + y). Additionally, the expression xy - y² can be factored as (√(xy) - y)(√(xy) + y). For example, substituting x = 8 and y = 2 demonstrates these identities clearly.

PREREQUISITES
  • Understanding of algebraic identities
  • Familiarity with factoring polynomials
  • Knowledge of square roots and their properties
  • Basic skills in substituting values into algebraic expressions
NEXT STEPS
  • Study algebraic identities, focusing on the difference of squares
  • Learn about polynomial factoring techniques
  • Explore the properties of square roots in algebra
  • Practice substituting values in algebraic expressions for verification
USEFUL FOR

Students studying algebra, educators teaching mathematical concepts, and anyone looking to deepen their understanding of polynomial identities and factoring techniques.

Atqiya
Messages
1
Reaction score
0
why x2 . y2 = (x-y) (x+y) and xy . y2 cannot be (x-y) (y+y)
 
Mathematics news on Phys.org
Atqiya said:
why x2 . y2 = (x-y) (x+y) and xy . y2 cannot be (x-y) (y+y)
If by x2 . y2 you mean ##x^2\cdot y^2##, then it is not equal to ##(x-y)(x+y)##.
It is true that ##x^2-y^2=(x-y)(x+y)##. It is also true that ##xy-y^2=(\sqrt{xy}-y)(\sqrt{xy}+y)## . Try substituting ##x=8## and ##y=2## to see how it works.
 
  • Like
Likes   Reactions: YoungPhysicist

Similar threads

  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 10 ·
Replies
10
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
4
Views
2K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 18 ·
Replies
18
Views
3K
Replies
1
Views
1K
  • · Replies 19 ·
Replies
19
Views
2K