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For each value of y greater than 2√3, the function f(x) is
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Author:  scc404 [ 14 Jan 2020, 17:58 ]
Post subject:  For each value of y greater than 2√3, the function f(x) is

Project IR Butler 2019-20 - Get one IR Question Everyday
Question # 107, Date : 15-Jan-2020
This post is a part of Project IR Butler 2019-20. Click here for Details


For each value of \(y\) greater than \(2 \sqrt{3}\), the function \(f(x)\) is such that the equation \(f(x) = y\) has a solution of the form \(x=\frac{y^2+12}{y}\)

Select one value for \(a\) and one value for \(b\) such that the given information implies \(f(a) = b\). Make only two selections, one in each column.

\(a\)\(b\)Values
1
2
4
6
8


Show SpoilerMy Question
Need help with this question. I don't understand how you know that because y is greater than \(2 \sqrt{3}\), then only choices available for \(b\) are 4, 6, and 8. How do you know that from "greater than \(2 \sqrt{3}\)"?


B: 6
A: 8

Author:  CAMANISHPARMAR [ 14 Jan 2020, 22:46 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

scc404 wrote:
Project IR Butler 2019-20 - Get one IR Question Everyday
Question # 107, Date : 15-Jan-2020
This post is a part of Project IR Butler 2019-20. Click here for Details


For each value of \(y\) greater than \(2 \sqrt{3}\), the function \(f(x)\) is such that the equation \(f(x) = y\) has a solution of the form \(x=\frac{y^2+12}{y}\)

Select one value for \(a\) and one value for \(b\) such that the given information implies \(f(a) = b\). Make only two selections, one in each column.

\(a\)\(b\)Values
1
2
4
6
8


Show SpoilerMy Question
Need help with this question. I don't understand how you know that because y is greater than \(2 \sqrt{3}\), then only choices available for \(b\) are 4, 6, and 8. How do you know that from "greater than \(2 \sqrt{3}\)"?


\(2 \sqrt{3}\) is less than 4 because \(\sqrt{3}\) is less than 2.

Hence:
a = 8 and b = 6

Author:  scc404 [ 15 Jan 2020, 18:08 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

doesn't that mean it has to be greater than 2 because it is 2 and a root which leaves the other numbers? I'm still confused by that.

Author:  CAMANISHPARMAR [ 15 Jan 2020, 20:53 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

scc404 wrote:
doesn't that mean it has to be greater than 2 because it is 2 and a root which leaves the other numbers? I'm still confused by that.


Could you please elaborate more on your question; I have not understood it.

Author:  lacabral [ 16 Jan 2020, 08:39 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

I am confused as to how we got b=4. If I plug in 4 for "b", the answer is 7. However, if I plug in a=4, and b=6, the answer becomes f(4)=4.
Where did I go wrong?

Author:  CAMANISHPARMAR [ 17 Jan 2020, 20:56 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

lacabral wrote:
I am confused as to how we got b=4. If I plug in 4 for "b", the answer is 7. However, if I plug in a=4, and b=6, the answer becomes f(4)=4.
Where did I go wrong?


You may be right, I did not like the question so much. Did you mean to say "a = 8 and NOT 4"? b = 6 seems to be ok. kindly show your calculations.

Author:  lacabral [ 18 Jan 2020, 04:14 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

CAMANISHPARMAR wrote:
lacabral wrote:
I am confused as to how we got b=4. If I plug in 4 for "b", the answer is 7. However, if I plug in a=4, and b=6, the answer becomes f(4)=4.
Where did I go wrong?


You may be right, I did not like the question so much. Did you mean to say "a = 8 and NOT 4"? b = 6 seems to be ok. kindly show your calculations.



Yes! Correct, I meant to type a=8, b=6. Thank you so much!

Author:  Sajjad1994 [ 23 Apr 2021, 03:53 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

Official Explanation

The formula may only be applied for y greater than \(2\sqrt{3}\), therefore, the only choices available for b are 4, 6, and 8.

If f(a) = b and b = 4, then, according to the formula,

\(a=\frac{4^2+12}{4}=\frac{28}{4}=7\)

Since 7 is not an option, b = 4 must not be part of the correct response.

If f(a) = b and b = 6, then, according to the formula,

\(a=\frac{6^2+12}{6}=\frac{48}{6}=8\)

Since 8 is an option, a = 8 and b = 6 must be the correct response.

The correct answer is 8.

The correct answer is 6.

Author:  MichaelWunsch [ 25 Apr 2021, 21:48 ]
Post subject:  Re: For each value of y greater than 2√3, the function f(x) is

I am confused as to how we got b=4

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