Can I multiply the denominator that is in a bracket?

Question

When I`m solving a simultaneous question, there is a fraction in a bracket with a square outside. Can I multiply the denominator to get rid of it? 

Answer 1

If you have a fraction, and you have to square it, then what you do is square both the numerator and denominator to get rid of the brackets.  For example,

 

[1 / 4]² = 1² / 4² = 1 / 16

 

 

No more brackets.

 

 

Another approach is to expand the fraction based on the exponent.

 

[1 / 4]² = [1 / 4] * [1 / 4]

 

 

Now we just multiply the numerators and denominators to get          1 / 16