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If f(x) = 2x^2 − 4 and g(x) = 2x, for what values of x will f(x) = g
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20 Feb 2021, 07:54
20 Feb 2021, 07:54
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If \(f(x) = 2x^2 − 4\) and \(g(x) = 2x\), for what values of x will \(f(x)= g(x)\)?
A. x = {1, 2}
B. x = {−1, 2}
C. x = {−1, −2}
D. x = {1, −2}
E. x = {−1, 1}
A. x = {1, 2}
B. x = {−1, 2}
C. x = {−1, −2}
D. x = {1, −2}
E. x = {−1, 1}
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If f(x) = 2x^2 − 4 and g(x) = 2x, for what values of x will f(x) = g
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20 Feb 2021, 07:59
20 Feb 2021, 07:59
GeminiHeat wrote:
If \(f(x) = 2x^2 − 4\) and \(g(x) = 2x\), for what values of x will \(f(x)= g(x)\)?
A. x = {1, 2}
B. x = {−1, 2}
C. x = {−1, −2}
D. x = {1, −2}
E. x = {−1, 1}
A. x = {1, 2}
B. x = {−1, 2}
C. x = {−1, −2}
D. x = {1, −2}
E. x = {−1, 1}
\(f(x) = g(x)\)
\(2x^2 − 4 = 2x\)
\(x^2 − 2 = x\)
\(x^2 − 2x - 4 = 0\)
\((x - 2)(x + 1) = 0\)
i.e. \(x = 2\) or \(-1\)
Hence, option B
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If f(x) = 2x^2 4 and g(x) = 2x, for what values of x will f(x) = g
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03 Jul 2021, 03:46
03 Jul 2021, 03:46
Given that \(f(x) = 2x^2 − 4\) and \(g(x) = 2x\)
f(x) = g(x)
=> \(2x^2 − 4\) = 2x
=> \(2x^2\) - 2x - 4 = 0
Divide both the sides by 2 we get
=> \(x^2\) - x - 2 = 0
=> \(x^2\) + x - 2x - 2 = 0
=> x(x+1) - 2(x+1) = 0
=> (x+1) * (x-2) = 0
=> x = -1 or 2
So, Answer will be B
Hope it helps!
To learn more about Functions watch the following video
f(x) = g(x)
=> \(2x^2 − 4\) = 2x
=> \(2x^2\) - 2x - 4 = 0
Divide both the sides by 2 we get
=> \(x^2\) - x - 2 = 0
=> \(x^2\) + x - 2x - 2 = 0
=> x(x+1) - 2(x+1) = 0
=> (x+1) * (x-2) = 0
=> x = -1 or 2
So, Answer will be B
Hope it helps!
To learn more about Functions watch the following video
