Hi I need help with this maths question pls

Place the following numbers in ascending order:
7, 4root2, 2root7, 3root5
Can someone also explain how u got the answer thanks

Reply 1

xOutcast

I would go about this by trying to put everything within the square root using your surds laws.

For example (not using your numbers to allow you to have a go!):
5 * root3 = root25 * root3 = root75
6 * root5 = root36 * root5 = root180
Therefore, 5root3 < 6root5 as root180 > root75.
This makes sense as 6 is larger than 5; and root 5 is larger than root 3, so it stands to reason that 6 * root5 > 5 * root3.

(edited 7 months ago)

Reply 2

Can'tDecideAName

To me I understand the comment above me but it feels like they got the root backwards as they have the five times the root not in it (though maybe I'm the one misreading it)

So you want 7, 4√2, 2√7, 3√5 in order?

I would try to put them all as unsimplified surds though,
7 = √49,
4√2 = √16 * √2,
2√7 = √4 * √7,
3√5 = √9 * √5,

(edited 7 months ago)

Reply 3