Solve: 1/(mn) - (mn-(m:1/n+n/m:(mn))) Complex Fraction Problem

Question

1mn(mn(m:1n+nm:(mn))=? \frac{1}{mn}-(mn-(m:\frac{1}{n}+\frac{n}{m}:(mn))=?

Video Solution

Solution Steps

00:00 Solve
00:07 Negative times positive is always negative
00:11 Division is also multiplication by the reciprocal
00:25 Let's move the division to the denominator
00:35 Let's simplify what we can
00:46 Negative times negative is always positive
00:50 And this is the solution to the question

Step-by-Step Solution

To solve this problem, follow these steps:

  • Simplify the innermost portion of the expression: (m:1n+nm:(mn)) (m:\frac{1}{n}+\frac{n}{m}:(mn)) .
  • We interpret m:1n m:\frac{1}{n} as mn m \cdot n , translating division by a fraction into multiplication.
  • The entire sub-expression becomes (mn+nm1mn) (m \cdot n + \frac{n}{m} \cdot \frac{1}{mn}) .
  • Recognize that nm1mn=nm2n=1m2 \frac{n}{m} \cdot \frac{1}{mn} = \frac{n}{m^2n} = \frac{1}{m^2} .
  • This simplifies to mn+1m2 mn + \frac{1}{m^2} .

Now simplify the outer expression:

  • Substitute back into the original expression:
  • The expression becomes 1mn(mn(mn+1m2)) \frac{1}{mn} - (mn - (mn + \frac{1}{m^2})) .
  • Calculate inside the bracket: mnmn1m2=1m2 mn - mn - \frac{1}{m^2} = -\frac{1}{m^2} .
  • Therefore, the expression becomes 1mn(1m2)=1mn+1m2 \frac{1}{mn} - (-\frac{1}{m^2}) = \frac{1}{mn} + \frac{1}{m^2} .

Therefore, the simplified form of the problem is 1mn+1m2 \frac{1}{mn} + \frac{1}{m^2} .

Answer

1mn+1m2 \frac{1}{mn}+\frac{1}{m^2}