Question

@mathmale Just number 13. I only got as far as writing down the question and putting 36 / 9 = 4.

Answer 1

What's the question?

Answer 2

9/36 = 1/4

Answer 3

OK: Let's focus on #13. It's true that 36/9=4, but under the radical, we have 9/36=1/4.
\[\sqrt{\frac{ 9x ^{4} }{ 36 }}=\frac{ \sqrt{9} \sqrt{x ^{4}}}{ \sqrt{36} }=?\]