1. If fog(x) = (2x-1)/x and g(x) = 5x + 2 find; a.) f(x) b.) The truth set of g^-1(x) + 3 = gof(x). 2. Find the measure of the obtuse angle between the lines 3x - 5y + 2 = 0 and x + 4y + 5 = 0
This mathematics problem involves applying core mathematical principles and formulas. Below you will find a complete step-by-step solution with detailed explanations for each step, helping you understand not just the answer but the method behind it.
ScanSolve AI Answer
Step 1: Find $f(x)$.
We are given $f(g(x)) = \frac{2x-1}{x}$ and $g(x) = 5x+2$.
Let $y = g(x)$. Then $y = 5x+2$.
To find $x$ in terms of $y$, we rearrange the equation:
$$y - 2 = 5x$$
$$x = \frac{y-2}{5}$$
Now substitute $x$ in the expression for $f(g(x))$:
$$f(y) = \frac{2\left(\frac{y-2}{5}\right)-1}{\frac{y-2}{5}}$$
$$f(y) = \frac{\frac{2y-4}{5}-1}{\frac{y-2}{5}}$$
To simplify the numerator, find a common denominator:
$$f(y) = \frac{\frac{2y-4-5}{5}}{\frac{y-2}{5}}$$
$$f(y) = \frac{\frac{2y-9}{5}}{\frac{y-2}{5}}$$
$$f(y) = \frac{2y-9}{y-2}$$
Replace $y$ with $x$ to find $f(x)$:
$$f(x) = \frac{2x-9}{x-2}$$
*a) $\boxed{f(x) = \frac{2x-9}{x-2}}$
Step 2: Find $g^{-1}(x)$.
Let $y = g(x) = 5x+2$.
To find the inverse, swap $x$ and $y$:
$$x = 5y+2$$
$$x-2 = 5y$$
$$y = \frac{x-2}{5}$$
So, $g^{-1}(x) = \frac{x-2}{5}$.
Step 3: Find $g \circ f(x)$.
We have $f(x) = \frac{2x-9}{x-2}$ and $g(x) = 5x+2$.
$$g(f(x)) = g\left(\frac{2x-9}{x-2}\right)$$
$$g(f(x)) = 5\left(\frac{2x-9}{x-2}\right) + 2$$
$$g(f(x)) = \frac{5(2x-9)}{x-2} + \frac{2(x-2)}{x-2}$$
$$g(f(x)) = \frac{10x-45+2x-4}{x-2}$$
$$g(f(x)) = \frac{12x-49}{x-2}$$
Step 4: Solve the equation $g^{-1}(x) + 3 = g \circ f(x)$.
Substitute the expressions for $g^{-1}(x)$ and $g \circ f(x)$:
$$\frac{x-2}{5} + 3 = \frac{12x-49}{x-2}$$
Simplify the left side:
$$\frac{x-2}{5} + \frac{15}{5} = \frac{x-2+15}{5} = \frac{x+13}{5}$$
Now the equation is:
$$\frac{x+13}{5} = \frac{12x-49}{x-2}$$
Cross-multiply:
$$(x+13)(x-2) = 5(12x-49)$$
$$x^2 - 2x + 13x - 26 = 60x - 245$$
$$x^2 + 11x - 26 = 60x - 245$$
Rearrange into a quadratic equation $ax^2+bx+c=0$:
$$x^2 + 11x - 60x - 26 + 245 = 0$$
$$x^2 - 49x + 219 = 0$$
Use the quadratic formula $x = \frac{-b \pm \sqrt{b^2-4ac}}{2a}$:
$$x = \frac{-(-49) \pm \sqrt{(-49)^2 - 4(1)(219)}}{2(1)}$$
$$x = \frac{49 \pm \sqrt{2401 - 876}}{2}$$
$$x = \frac{49 \pm \sqrt{1525}}{2}$$
Simplify the square root: $\sqrt{1525} = \sqrt{25 \times 61} = 5\sqrt{61}$.
$$x = \frac{49 \pm 5\sqrt{61}}{2}$$
The values of $x$ must not make any denominator zero. For $f(x)$ and $g(f(x))$, $x-2 \neq 0$, so $x \neq 2$. The solutions found are not equal to 2.
*b) The truth set is $\boxed{\left\{\frac{49 - 5\sqrt{61}}{2}, \frac{49 + 5\sqrt{61}}{2}\right\}}$
Step 5: Find the slopes of the lines.
The first line is $3x - 5y + 2 = 0$.
Rearrange to slope-intercept form $y = mx+c$:
$$5y = 3x + 2$$
$$y = \frac{3}{5}x + \frac{2}{5}$$
The slope of the first line is $m_1 = \frac{3}{5}$.
The second line is $x + 4y + 5 = 0$.
Rearrange to slope-intercept form $y = mx+c$:
$$4y = -x - 5$$
$$y = -\frac{1}{4}x - \frac{5}{4}$$
The slope of the second line is $m_2 = -\frac{1}{4}$.
Step 6: Calculate the angle between the lines.
The formula for the angle $\theta$ between two lines with slopes $m_1$ and $m_2$ is:
$$\tan \theta = \left| \frac{m_1 - m_2}{1 + m_1 m_2} \right|$$
Substitute the slopes:
$$\tan \theta = \left| \frac{\frac{3}{5} - \left(-\frac{1}{4}\right)}{1 + \left(\frac{3}{5}\right)\left(-\frac{1}{4}\right)} \right|$$
$$\tan \theta = \left| \frac{\frac{3}{5} + \frac{1}{4}}{1 - \frac{3}{20}} \right|$$
Calculate the numerator:
$$\frac{3}{5} + \frac{1}{4} = \frac{12}{20} + \frac{5}{20} = \frac{17}{20}$$
Calculate the denominator:
$$1 - \frac{3}{20} = \frac{20}{20} - \frac{3}{20} = \frac{17}{20}$$
Substitute these values back into the formula:
$$\tan \theta = \left| \frac{\frac{17
Q
1. If fog(x) = (2x-1)/x and g(x) = 5x + 2 find; a.) f(x) b.) The truth set of g^-1(x) + 3 = gof(x). 2. Find the measure of the obtuse angle between the lines 3x - 5y + 2 = 0 and x + 4y + 5 = 0
|Mathematics
1. If fog(x) = (2x-1)/x and g(x) = 5x + 2 find; a.) f(x) b.) The truth set of g^-1(x) + 3 = gof(x). 2. Find the measure of the obtuse angle between the lines 3x - 5y + 2 = 0 and x + 4y + 5 = 0
ScanSolve AI Answer
Step 1: Find f(x).
We are given f(g(x))=x2x−1 and g(x)=5x+2.
Let y=g(x). Then y=5x+2.
To find x in terms of y, we rearrange the equation:
y−2=5xx=5y−2
Now substitute x in the expression for f(g(x)):
f(y)=5y−22(5y−2)−1f(y)=5y−252y−4−1
To simplify the numerator, find a common denominator:
f(y)=5y−252y−4−5f(y)=5y−252y−9f(y)=y−22y−9
Replace y with x to find f(x):
f(x)=x−22x−9
*a) f(x)=x−22x−9
Step 2: Find g−1(x).
Let y=g(x)=5x+2.
To find the inverse, swap x and y:
x=5y+2x−2=5yy=5x−2
So, g−1(x)=5x−2.
Step 3: Find g∘f(x).
We have f(x)=x−22x−9 and g(x)=5x+2.
g(f(x))=g(x−22x−9)g(f(x))=5(x−22x−9)+2g(f(x))=x−25(2x−9)+x−22(x−2)g(f(x))=x−210x−45+2x−4g(f(x))=x−212x−49
Step 4: Solve the equation g−1(x)+3=g∘f(x).
Substitute the expressions for g−1(x) and g∘f(x):
5x−2+3=x−212x−49
Simplify the left side:
5x−2+515=5x−2+15=5x+13
Now the equation is:
5x+13=x−212x−49
Cross-multiply:
(x+13)(x−2)=5(12x−49)x2−2x+13x−26=60x−245x2+11x−26=60x−245
Rearrange into a quadratic equation ax2+bx+c=0:
x2+11x−60x−26+245=0x2−49x+219=0
Use the quadratic formula x=2a−b±b2−4ac:
x=2(1)−(−49)±(−49)2−4(1)(219)x=249±2401−876x=249±1525
Simplify the square root: 1525=25×61=561.
x=249±561
The values of x must not make any denominator zero. For f(x) and g(f(x)), x−2=0, so x=2. The solutions found are not equal to 2.
*b) The truth set is {249−561,249+561}
Step 5: Find the slopes of the lines.
The first line is 3x−5y+2=0.
Rearrange to slope-intercept form y=mx+c:
5y=3x+2y=53x+52
The slope of the first line is m1=53.
The second line is x+4y+5=0.
Rearrange to slope-intercept form y=mx+c:
4y=−x−5y=−41x−45
The slope of the second line is m2=−41.
Step 6: Calculate the angle between the lines.
The formula for the angle θ between two lines with slopes m1 and m2 is:
tanθ=1+m1m2m1−m2
Substitute the slopes:
tanθ=1+(53)(−41)53−(−41)tanθ=1−20353+41
Calculate the numerator:
53+41=2012+205=2017
Calculate the denominator:
1−203=2020−203=2017
Substitute these values back into the formula:
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