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If = 2x2 + 2, which of the following is equal to ? (A) (B) (
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Updated on: 31 Oct 2024, 15:34
Updated on: 31 Oct 2024, 15:34
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Question Stats:
67% (01:02) correct
32% (00:56) wrong based on 49 sessions
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If \(\Large \ulcorner x= 2x^2 + 2\), which of the following is equal to \(\Large \ulcorner 4\) ?
(A) \( \Huge \ulcorner \LARGE \ulcorner -1\)
(B) \(\Large \ulcorner -2\)
(C) \(\Large \ulcorner 2\)
(D) \(\Large \ulcorner 17\)
(E) \(\Large \ulcorner 34\)
(A) \( \Huge \ulcorner \LARGE \ulcorner -1\)
(B) \(\Large \ulcorner -2\)
(C) \(\Large \ulcorner 2\)
(D) \(\Large \ulcorner 17\)
(E) \(\Large \ulcorner 34\)
Re: If = 2x2 + 2, which of the following is equal to ? (A) (B) (
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25 Jul 2018, 20:27
25 Jul 2018, 20:27
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sandy wrote:
If \(\alpha(x)= 2x^2 + 2\), which of the following is equal to \(\alpha(4)\) ?
(A) \(\alpha(\alpha(-1))\)
(B) \(\alpha(-2)\)
(C) \(\alpha(\alpha(2))\)
(D) \(\alpha(17)\)
(E) \(\alpha(34)\)
(A) \(\alpha(\alpha(-1))\)
(B) \(\alpha(-2)\)
(C) \(\alpha(\alpha(2))\)
(D) \(\alpha(17)\)
(E) \(\alpha(34)\)
Given
\(\alpha(x)= 2x^2 + 2\)
we can find out the value of \(\alpha(4)\).
\(\alpha(4)\)
\(\alpha(4) = 2.(4)^2 +2 = 34\)
So we have to find out an answer choice that matches the result.
Option A)
\(\alpha(\alpha(-1))\)
This option has 2 parts. we can segregate them to calculate easily.
\(\alpha(-1) = 2*(-1)^2 + 2 = 4\)
Now we have determine the value of \(\alpha(4)\), which is exactly the same as question stem and we have already found out the value of \(\alpha(4)\)
The best answer is A.
Re: If = 2x2 + 2, which of the following is equal to ? (A) (B) (
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31 Jul 2018, 14:30
31 Jul 2018, 14:30
Expert Reply
Explanation
To answer the question, “If \(\alpha (x)= 2x^2 + 2\), which of the following is equal to \(\alpha (x)\)?” plug 4 into the given function.
\(\alpha (4)= 2(4)^2 + 2\)
\(\alpha (4)= 34\)
Do not fall for trap answer choice (E). The correct answer is 34, which does not appear in the choices in that form. Trap choice (E) is \(\alpha (34)\) , which equals \(2(34)^2 + 2\); this is much greater than 34.
Instead, solve each answer choice until one equals 34. Choice (A), \(\alpha (\alpha (-1))\), uses the function symbol twice, so plug –1 into the function, then plug the resulting answer back into the function again:
\(\alpha(-1)= 2(–1)^2 + 2 = 4\)
\(\alpha(4)= 2(4)^2 + 2 = 34\)
To answer the question, “If \(\alpha (x)= 2x^2 + 2\), which of the following is equal to \(\alpha (x)\)?” plug 4 into the given function.
\(\alpha (4)= 2(4)^2 + 2\)
\(\alpha (4)= 34\)
Do not fall for trap answer choice (E). The correct answer is 34, which does not appear in the choices in that form. Trap choice (E) is \(\alpha (34)\) , which equals \(2(34)^2 + 2\); this is much greater than 34.
Instead, solve each answer choice until one equals 34. Choice (A), \(\alpha (\alpha (-1))\), uses the function symbol twice, so plug –1 into the function, then plug the resulting answer back into the function again:
\(\alpha(-1)= 2(–1)^2 + 2 = 4\)
\(\alpha(4)= 2(4)^2 + 2 = 34\)
