Saved Bookmarks
| 1. |
Express (xsquare-1by ysquare)(ysquare-1by xsquare)as a perfect square |
|
Answer» Now, (x² - 1/y²) (y² - 1/x²) = x²y² - x²/x² - y²/y² + 1/(x²y²) = (xy)² - 1 - 1 + 1/(xy)² = (xy)² - 2 + 1/(xy)² = (xy)² - 2 (xy) (1/xy) + 1/(xy)² = (xy - 1/xy)², which is a PERFECT square We used the IDENTITY - (a - B)² = a² - 2ab + b² # |
|