F(x) = -x² + 4
g(x) = 6x
(g - f)(3) = 6(3) - (-(3)² + 4)
(g - f)(3) = 18 - (-9 + 4)
(g - f)(3) = 18 - (-5)
(g - f)(3) = 18 + 5
(g - f)(3) = 23
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4 cos² x - 3 = 0
4 cos² x = 3
cos² x = 3/4
cos x = ±(√3)/2
Fixing the squared cosine doesn't discriminate among quadrants. There's one in every quadrant
cos x = ± cos(π/6)
Let's do plus first. In general, cos x = cos a has solutions x = ±a + 2πk integer k
cos x = cos(π/6)
x = ±π/6 + 2πk
Minus next.
cos x = -cos(π/6)
cos x = cos(π - π/6)
cos x = cos(5π/6)
x = ±5π/6 + 2πk
We'll write all our solutions as
x = { -5π/6, -π/6, π/6, 5π/6 } + 2πk integer k
The answer to the question is b
It is 1.55 times the value of the second number.