MHB Find the value of x square + y square

  • Thread starter Thread starter mathlearn
  • Start date Start date
  • Tags Tags
    Square Value
Click For Summary
To find the value of x² + y² given x - y = 1 and x²y - xy² = 2, the second equation can be factored to xy(x - y) = 2. Substituting x - y = 1 into this equation yields xy = 2. Using the identity x² + y² = (x - y)² + 2xy, we can calculate x² + y² as (1)² + 2(2), resulting in a final value of 5. The solution demonstrates the effective use of algebraic manipulation to derive the answer.
mathlearn
Messages
331
Reaction score
0
If x-y= 1 & x2y - xy2 =2, Find the value of x2+y2

Any Ideas on how to begin?

Many Thanks :)
 
Mathematics news on Phys.org
mathlearn said:
If x-y= 1 & x2y - xy2 =2, Find the value of x2+y2

Any Ideas on how to begin?

Many Thanks :)

you can factor 2nd equation to get xy(x-y) = 2.
now put from 1st equation value of x-y to get xy * 1 = 2 or xy =2

now $(x^2+y^2) = (x-y)^2 + 2xy = 1 ^2 + 2 * 2 = 5$
 
kaliprasad said:
you can factor 2nd equation to get xy(x-y) = 2.
now put from 1st equation value of x-y to get xy * 1 = 2 or xy =2

now $(x^2+y^2) = (x-y)^2 + 2xy = 1 ^2 + 2 * 2 = 5$

Many Thanks :)
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

Similar threads

  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 19 ·
Replies
19
Views
3K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 13 ·
Replies
13
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 4 ·
Replies
4
Views
3K