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Secondary 1 | Maths
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SlyFox
SlyFox

Secondary 1 chevron_right Maths chevron_right Singapore

I really don’t see how bi) can help me solve bii). Would appreciate it if someone could explain. Thank you!

Date Posted: 4 years ago
Views: 282

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Eric Nicholas K
Eric Nicholas K's answer
5997 answers (Tutor Details)
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It’s remarkable how this is given as a Sec 1 Maths question, considering that this is usually dished out only in Sec 2.

Nevertheless, an idea here is to square the expression x - 1/x, just like previously done in part a for x + 1/x.

Note that square rooting both sides of an equation to get rid of the square on one side results in a +- on the other side.

Because 0 < x < 1, x is a decimal between 0 and 1. As such, 1 divided by x will definitely be more than 1, since 1 is bigger than any such decimal (a larger number divided by a smaller number always exceeds 1).

As such, we can only take the negative value for x - 1/x.
SlyFox
SlyFox
4 years ago
Thank you!!!!