Click to see the original problem
Please explain secondlast to last step
Answer provided by our tutors
We sugest you solve by intervals using the definition for absolute value
So, if both m,n > 0 or both m,n <0 the expresion becomes:
if m>0 and n < 0, or m <0 and n > 0 the expression becomes:
If m = 0 or n = 0 the expression is not defined because of the division by '0'.