
the denominator cannot be zero, because the division by zero is not defined, therefore:
![\begin{gathered} x^2-9=0 \\ \text{Solving for x:} \\ x^2=9 \\ \sqrt[]{x^2}=\sqrt[]{9} \\ x=\pm3 \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20x%5E2-9%3D0%20%5C%5C%20%5Ctext%7BSolving%20for%20x%3A%7D%20%5C%5C%20x%5E2%3D9%20%5C%5C%20%5Csqrt%5B%5D%7Bx%5E2%7D%3D%5Csqrt%5B%5D%7B9%7D%20%5C%5C%20x%3D%5Cpm3%20%5Cend%7Bgathered%7D)
Therefore the domain of (f o g)(x) is:
In the rhombus, the diagonals are perpendicular.
We know, the sum of the measures of the triangle is equal 180°.
Therefore we have the equation:

<em>combine like terms</em>

<em>subtract 75 from both sides</em>
<em>divide both sides by 5</em>

<h3>Answer: x = 21°</h3>
Hello.
1. Switch y and x.
x = 10y^2 - 4
2. Isolate y.
x + 4 = 10y^2
(x + 4)/(10) = y^2
y = sqrt[(x + 4)/(10)]
3. Replace y with f^-1(x)
f^-1(x) = sqrt[(x + 4)/(10)]
Good luck to you!
These are "composite" functions.
g(x+a) means insert (x+a) into g(x) to replace every x:
g(x+a) - g(x) = -5(x+a)^2 +4(x+a) +5x^2 - 4x
= -5(x^2 + 2ax + a^2) +4x +4a + 5x^2 - 4x
Now just Multiply and sum up the answer.