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The function f is defined by
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02 Dec 2020, 09:23
02 Dec 2020, 09:23
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The function \(f\) is defined by \(f(x)=\sqrt{x^2}\). For which of the following values of x is \(f(x)=x\) ?
Indicate all such values.
A. −10,000
B. −1
C. −.00001
D. 0
E. .00001
F. 10,000
Kudos for the right answer and explanation
Indicate all such values.
A. −10,000
B. −1
C. −.00001
D. 0
E. .00001
F. 10,000
Kudos for the right answer and explanation
Re: The function f is defined by
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02 Jan 2021, 01:38
02 Jan 2021, 01:38
1
Carcass wrote:
The function \(f\) is defined by \(f(x)=\sqrt{x^2}\). For which of the following values of x is \(f(x)=x\) ?
Indicate all such values.
A. −10,000
B. −1
C. −.00001
D. 0
E. .00001
F. 10,000
Kudos for the right answer and explanation
Indicate all such values.
A. −10,000
B. −1
C. −.00001
D. 0
E. .00001
F. 10,000
Kudos for the right answer and explanation
Any number squared will yield a positive number.
If we check option B: -1 x -1 = 1, so f(-1) = √1 and √1 = 1 , hence f(x) is not equal to x.
In the same way we can eliminate A and C because they are negative.
0 x 0 is 0 and √0 = 0, option D is satisfying the condition.
0.00001 x 0.00001 = 0.0000000001 but √0.0000000001 = 0.00001, so option E is getting satisfied.
Square root of 10000 x 10000 = 10000, option F is also getting satisfied.
Therefore the correct answer options are D, E & F.
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The function f is defined by
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07 Aug 2022, 10:19
07 Aug 2022, 10:19
1
Given that \(f(x)=\sqrt{x^2}\) and we need to find the value of x for which \(f(x)=x\)
\(f(x)=\sqrt{x^2}\) = x (given)
=> |x| = x (Watch this video to learn about the Basics of Absolute Value)
Now, |x| = x is true only for non negative values of x, as |x| can never be negative
Only non-negative values in the option choices are 0, .00001 and 10,000
So, Answer will be D, E, F.
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
\(f(x)=\sqrt{x^2}\) = x (given)
=> |x| = x (Watch this video to learn about the Basics of Absolute Value)
Now, |x| = x is true only for non negative values of x, as |x| can never be negative
Only non-negative values in the option choices are 0, .00001 and 10,000
So, Answer will be D, E, F.
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
