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# Why? watch

1. .

Simple enough, I managed to deduce that .

What I don't understand, however, is how can also equal in this instance, because if , and , that's , which seems to equal , rather than

Could someone explain how could be in this instance?
2. (Original post by Illidan2)
.

Simple enough, I managed to deduce that .

What I don't understand, however, is how can also equal in this instance, because if , and , that's , which seems to equal , rather than

Could someone explain how could be in this instance?
when you square root both sides you get 2x-3 = +/- 3
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3. Ahh yes. Of course. I always seem to overlook that. I must remember that the square root may also be the negative variant. Thank you.
4. (Original post by Illidan2)
Ahh yes. Of course. I always seem to overlook that. I must remember that the square root may also be the negative variant. Thank you.
One thing, unless x<0.
|x| just means the positive value.
So , however -3 is a solution to the equation.

This is important, because in later questions, you can't just square root a value and say it is equal to 2 different values.

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