Note that f(x) as given is <em>not</em> invertible. By definition of inverse function,
which is a cubic polynomial in 
with three distinct roots, so we could have three possible inverses, each valid over a subset of the domain of f(x).
Choose one of these inverses by restricting the domain of f(x) accordingly. Since a polynomial is monotonic between its extrema, we can determine where f(x) has its critical/turning points, then split the real line at these points.
f'(x) = 3x² - 1 = 0 ⇒ x = ±1/√3
So, we have three subsets over which f(x) can be considered invertible.
• (-∞, -1/√3)
• (-1/√3, 1/√3)
• (1/√3, ∞)
By the inverse function theorem,
where f(a) = b.
Solve f(x) = 2 for x :
x³ - x + 2 = 2
x³ - x = 0
x (x² - 1) = 0
x (x - 1) (x + 1) = 0
x = 0 or x = 1 or x = -1
Then 
can be one of
• 1/f'(-1) = 1/2, if we restrict to (-∞, -1/√3);
• 1/f'(0) = -1, if we restrict to (-1/√3, 1/√3); or
• 1/f'(1) = 1/2, if we restrict to (1/√3, ∞)
A diagram would surely help here. But imagine that you stand at spot A and someone finds that your distance from the base of the building is 42 feet. Call this point B.
Imagine a vertical line from that spot, straight up. Label the top of this line C.
The acute angle at A is 67 degrees. You want to find the height of the building, which would be the length of the "opposite side of triangle ABC."
The length of the "adjacent side of triangle ABC" would be 42 feet.
We don't know the length of the hypotenuse, altho' we could easilyl calculate it using the Pyth. Them.
We choose the tangent function to solve for the height of the building (which is the length of the opposite side.
height
By definition, tangent (67 degrees) = -------------------------------------
42 feet
Find tan 67. Multiply your result by 42 feet. This product is the height of the building.
Since you have an equation equal to both x and y, you can either substitute the equation equal to x for x or the equation equal to y for y.
x=y-1
y=4-2x
I would substitute the y in using 4-2x
x=(4-2x)-1
x=3-2x
3x=3
x=1
Then plug in x and solve for y
1=y-1
2=y
Hello!
You know that two sides and one of the angles are congruent
The only choice that has two sides and 1 angle is ASA postulate
The answer is ASA postulate
Hope this helps!
