Solve: mn-(3mn-n/m:m/n+nm/3:m²) Complex Algebraic Expression

Question

mn(3mnnm:mn+nm3:m2)=? mn-(3mn-\frac{n}{m}:\frac{m}{n}+\frac{nm}{3}:m^2)=\text{?}

Video Solution

Solution Steps

00:00 Solve
00:09 Division is also multiplication by the reciprocal
00:20 Move the division to the denominator
00:28 Make sure to multiply numerator by numerator and denominator by denominator
00:31 Simplify what's possible
00:40 Negative times positive is always negative
00:44 Negative times negative is always positive
00:50 Negative times positive is always negative
00:57 Collect like terms
01:05 And this is the solution to the question

Step-by-Step Solution

To solve this expression, we will simplify it step by step:

The expression to simplify is:

mn(3mnnm:mn+nm3:m2) mn - \left(3mn - \frac{n}{m} : \frac{m}{n} + \frac{nm}{3} : m^2 \right)

First, simplify each term within the parentheses:

  • The division nm:mn\frac{n}{m} : \frac{m}{n} can be rewritten as nmnm\frac{n}{m} \cdot \frac{n}{m} because mn\frac{m}{n} inverted becomes nm\frac{n}{m}. This results in n2m2\frac{n^2}{m^2}.
  • Next, the operation nm3:m2\frac{nm}{3} : m^2 is rewritten as nm31m2\frac{nm}{3} \cdot \frac{1}{m^2}. This simplifies to n3m\frac{n}{3m} because mm=m2m \cdot m = m^2.

Substitute these simplified forms back into the expression inside the parentheses:

3mnn2m2+n3m 3mn - \frac{n^2}{m^2} + \frac{n}{3m}

Now rewrite the entire expression outside of the parentheses and solve:

mn(3mnn2m2+n3m) mn - \left( 3mn - \frac{n^2}{m^2} + \frac{n}{3m} \right)

Use distributive law to expand:

mn3mn+n2m2n3m mn - 3mn + \frac{n^2}{m^2} - \frac{n}{3m}

Combine like terms:

2mn+n2m2n3m -2mn + \frac{n^2}{m^2} - \frac{n}{3m}

Therefore, the solution to the simplified expression is:

2mn+n2m2n3m -2mn + \frac{n^2}{m^2} - \frac{n}{3m}

Answer

2mn+n2m2n3m -2mn+\frac{n^2}{m^2}-\frac{n}{3m}