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April 5th, 2017, 12:20 AM   #11
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thank you for asking, I think I do because the x is positive, and even though it says negative it would still be 1 since it's one space no matter which way we go?
In order for $\sqrt{\text{anything}}$ to be defined, the anything has to be greater than or equal to 0.

So if the anything is $x - 1$, we must have $x - 1 \geq 0$ which implies $x \geq 1$. Does that make sense?
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April 5th, 2017, 07:09 AM   #12
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In order for $\sqrt{\text{anything}}$ to be defined, the anything has to be greater than or equal to 0.

So if the anything is $x - 1$, we must have $x - 1 \geq 0$ which implies $x \geq 1$. Does that make sense?
Thanks for asking and for helping, I am not sure if it makes sense to me as unless it just does not happen with square roots can't we have -00 which means it could be equal to or less than.
and of course if I don't make senses it's just because my knowledge and understanding is not there yet or if it is I just don't yet possibly get the connection yet.
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April 5th, 2017, 08:44 AM   #13
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Thanks for asking and for helping, I am not sure if it makes sense to me as unless it just does not happen with square roots can't we have -00 which means it could be equal to or less than.
and of course if I don't make senses it's just because my knowledge and understanding is not there yet or if it is I just don't yet possibly get the connection yet.
Do you know what is the domain of the square root function? That's the place to start.
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April 5th, 2017, 12:55 PM   #14
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Do you know what is the domain of the square root function? That's the place to start.
I think so is it just what number do we get when a number multiplied by it's self ?
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April 5th, 2017, 01:00 PM   #15
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I think so is it just what number do we get when a number multiplied by it's self ?
Ah. No. There's a more fundamental issue. Two in fact.

The question was, do you know what is the domain of the square root function? We're given a function and we need to find its domain. So,

* Do you know what a function is?

* Do you know what the domain of a function is?

If those aren't clear let's talk about them.
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April 5th, 2017, 01:27 PM   #16
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oh boo sorry, I think a function has been explained to me as the input to a output, yet I always only look at it has what we replace x with or what we move to where X is.

I think the domain of the function is our x
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April 5th, 2017, 01:55 PM   #17
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oh boo sorry, I think a function has been explained to me as the input to a output, yet I always only look at it has what we replace x with or what we move to where X is.

I think the domain of the function is our x
Ok. Then what is the domain of the square root function? What real numbers $x$ can you legally input to $\sqrt{x}$?
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April 5th, 2017, 02:51 PM   #18
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Ok. Then what is the domain of the square root function? What real numbers $x$ can you legally input to $\sqrt{x}$?
I think this is where we can use any number sorry if I am wrong.
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April 5th, 2017, 02:57 PM   #19
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I think this is where we can use any number sorry if I am wrong.
Ok, let's try out some numbers.

What happens when we put 4 into the square root function? What comes out?

How about if we input 1?

How about 0?

How about -1?

Four questions, requires four answers. Bearing in mind that we are living in the real numbers.
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April 5th, 2017, 04:01 PM   #20
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Ok, let's try out some numbers.

What happens when we put 4 into the square root function? What comes out?

How about if we input 1?

How about 0?

How about -1?

Four questions, requires four answers. Bearing in mind that we are living in the real numbers.
Okay thanks if I did it right looks like it has to be zero or a positive number and can't be negative.
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