InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
Simplify the following: (i) (x - 2y) (y – 3x) + (x + y) (x - 3y) – (y – 3x) (4x – 5y)(ii) (m + n) (m2 – mn + n2 ) |
|
Answer» i) (x – 2y) (y – 3x) + (x + y) (x – 3y) – (y – 3x) (4x – 5y) = (y – 3x) [x – 2y – (4x – 5y)] + (x + y)(x – 3y) = (y – 3x) [x – 2y – 4x + 5y] + (x + y) (x – 3y) = (y – 3x) (3y – 3x) + (x + y) (x – 3y) = y(3y – 3x) – 3x(3y – 3x) + x(x – 3y) + y(x – 3y) = 3y2 – 3xy – 9xy + 9x2 + x2 – 3xy + xy – 3y2 = 10x2 – 14xy ii) (m + n) (m2 – mn + n2) = m(m2 – mn + n2) + n(m2 – mn + n2) = m3 – m2n + n2m + nm2 – mn2 + n3 = m3 + n3 |
|