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If h(x) = 2x3 – 3 and h(m) = –19, what is the value of m?
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25 Jul 2018, 17:10
25 Jul 2018, 17:10
Expert Reply
00:00
Question Stats:
91% (00:42) correct
8% (01:55) wrong based on 61 sessions
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If \(h(x) = 2x^3 - 3\) and \(h(m) = -19\), what is the value of m?
(A) –3
(B) –2
(C) 2
(D) 6,856
(E) 6,862
(A) –3
(B) –2
(C) 2
(D) 6,856
(E) 6,862
Re: If h(x) = 2x3 – 3 and h(m) = –19, what is the value of m?
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31 Jul 2018, 14:15
31 Jul 2018, 14:15
Expert Reply
Explanation
Be careful with the notation here. The problem indicates that \(h(m) = -19\), not that \(h(-19) =\) something else. Do not plug –19 in for x; rather, plug m in for x and set the answer equal to –19:
\(2m^3 - 3 = -19\)
\(2m^3 = -16\)
\(m^3 = -8\)
\(m = –2\)
Hence option B i correct!
Be careful with the notation here. The problem indicates that \(h(m) = -19\), not that \(h(-19) =\) something else. Do not plug –19 in for x; rather, plug m in for x and set the answer equal to –19:
\(2m^3 - 3 = -19\)
\(2m^3 = -16\)
\(m^3 = -8\)
\(m = –2\)
Hence option B i correct!
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Re: If h(x) = 2x3 3 and h(m) = 19, what is the value of m?
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24 Aug 2022, 09:45
24 Aug 2022, 09:45
Given that \(h(x) = 2x^3 - 3\) and \(h(m) = -19\) and we need to find the value of m
To find h(m) we need to compare what is inside the bracket () in h(m) and h(x)
=> We need to substitute x with m in \(h(x) = 2x^3 - 3\) to get the value of h(m)
=> \(h(m) = 2m^3 - 3\) = -19 (given)
=> \(2m^3\) = -19 + 3 = -16
=> \(m^3\) = \(\frac{-16}{2}\) = -8 = \((-2)^3\)
=> m = -2
So, Answer will be B
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
To find h(m) we need to compare what is inside the bracket () in h(m) and h(x)
=> We need to substitute x with m in \(h(x) = 2x^3 - 3\) to get the value of h(m)
=> \(h(m) = 2m^3 - 3\) = -19 (given)
=> \(2m^3\) = -19 + 3 = -16
=> \(m^3\) = \(\frac{-16}{2}\) = -8 = \((-2)^3\)
=> m = -2
So, Answer will be B
Hope it helps!
Watch the following video to learn the Basics of Functions and Custom Characters
