Both, because when you square root 4 for example you can have 2 but if you square -2 (-2 * -2) you'll get positive 4 as well so there's 2 possibities and you must list both or you'll lose an easy mark! Technically you'd say 'Or' rather than 'and'. They like doing this in C1 with rearrangement questions, I would write it as +/- 4/3
Thanks and yes thats exactly how i wrote out my answer. Cheers for advice.
Both, because when you square root 4 for example you can have 2 but if you square -2 (-2 * -2) you'll get positive 4 as well so there's 2 possibities and you must list both or you'll lose an easy mark! Technically you'd say 'Or' rather than 'and'. They like doing this in C1 with rearrangement questions, I would write it as +/- 4/3
Wow thanks I've been doing it wrong all this time. Guess I've never been called out because the mark schemes condone it but it's useful to know, didn't realise you only did +/- with algebrea, cheers 👍🏼
It is true that (-4/3)squared takes you back to 16/9 but by convention the square root always refers to the positive part. (Another way to write mod x is square root of x^2, try it on desmos!)