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If f(x) = x2 – 1, what is the value of f(y) + f(–1)?
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25 Jul 2018, 17:12
25 Jul 2018, 17:12
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Expert Reply
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Question Stats:
95% (00:27) correct
4% (00:56) wrong based on 65 sessions
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If \(f(x) = x^2 - 1\), what is the value of \(f(y) + f(-1)\)?
(A) \(y^2 - 1\)
(B) \(y^2\)
(C) \(y^2 + 1\)
(D) \(y^2 - 2y\)
(E) \(y^2 - 2y - 1\)
(A) \(y^2 - 1\)
(B) \(y^2\)
(C) \(y^2 + 1\)
(D) \(y^2 - 2y\)
(E) \(y^2 - 2y - 1\)
Re: If f(x) = x2 – 1, what is the value of f(y) + f(–1)?
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31 Jul 2018, 14:22
31 Jul 2018, 14:22
Expert Reply
Explanation
The question requires plugging y into the function, then plugging –1 into the function, then summing the two results:
\(f(y) = y^2 - 1\)
\(f(-1) = (-1)^2 - 1\)
\(f(-1) = 0\)
Thus, \(f(y) + f(-1) = y^2 - 1 + 0 = y^2 - 1\).
The question requires plugging y into the function, then plugging –1 into the function, then summing the two results:
\(f(y) = y^2 - 1\)
\(f(-1) = (-1)^2 - 1\)
\(f(-1) = 0\)
Thus, \(f(y) + f(-1) = y^2 - 1 + 0 = y^2 - 1\).
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If f(x) = x2 1, what is the value of f(y) + f(1)?
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03 Dec 2024, 17:50
03 Dec 2024, 17:50
1
\(f(x) = x^2 - 1\) and we need to find the value of \(f(y) + f(-1)\)
To find f(y) we will substitute x with y in \(f(x) = x^2 - 1\)
=> \(f(y) = y^2 - 1\)
Similarly, \(f(-1) = (-1)^2 - 1\) = 1 - 1 = 0
=> f(y) + f(-1) = \(y^2 - 1 + 0\) = \(y^2 - 1\)
So, Answer will be A
Hope it helps!
Watch the following video to MASTER Functions and Custom Characters
To find f(y) we will substitute x with y in \(f(x) = x^2 - 1\)
=> \(f(y) = y^2 - 1\)
Similarly, \(f(-1) = (-1)^2 - 1\) = 1 - 1 = 0
=> f(y) + f(-1) = \(y^2 - 1 + 0\) = \(y^2 - 1\)
So, Answer will be A
Hope it helps!
Watch the following video to MASTER Functions and Custom Characters
