question_answer

Add and Subtract:

(a) m - n, m + n

(b) mn + 5 - 2, mn + 3.

Answer:

(a) (m - n) + (m + n) = m - n 4- m + n

= m + m ? n + n

= (1 + l) m+ (-1+ 1)71

= 2m

And, (m - n) - (m + n) = m ? n ? m - n

= m ? m ? n - n

= (1 - l)m + (- 1 - l)n

= 0m+ (-2)n

(b) (mn + 5 - 2) + (mn + 3) = (mn + 3) + (mn + 3) = 2mn + 6

(mn + 5-2) - (mn + 3)=(mn + 3) - (mn + 3)= 0