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Example Questions
Example Question #61 : How To Find F(X)
When we multiply a function by a constant, we multiply each value in the function by that constant. Thus, 2f(x) = 4x + 12. We then subtract g(x) from that function, making sure to distribute the negative sign throughout the function. Subtracting g(x) from 4x + 12 gives us 4x + 12 - (3x - 3) = 4x + 12 - 3x + 3 = x + 15. We then add 2 to x + 15, giving us our answer of x + 17.
Example Question #101 : Algebraic Functions
Given the following functions, evaluate .
Example Question #61 : How To Find F(X)
The point is one of the points of intersection of the graphs of and . Given that and , find the value of .
Since it’s given than , we know that . We now know that (3, 7) is a point of intersection. Therefore, as well. In other words, , so .
Example Question #63 : How To Find F(X)
Consider these functions:
Which of the following is equivalent to ?
Example Question #62 : How To Find F(X)
If , what is the smallest possible value of ?
4
8
6
12
10
6
This equation describes a parabola whose vertex is located at the point (4, 6). No matter how large or small the value of t gets, the smallest that f(t) can ever be is 6 because the parabola is concave up. To prove this to yourself you can plug in different values of t and see if you ever get anything smaller than 6.
Example Question #13 : Algebraic Functions
If , then ?
To find when , we substitute for in .
Thus, .
We expand to .
We can combine like terms to get .
We add 3 to this result to get our final answer.
Example Question #63 : How To Find F(X)
Let and be functions such that , and . Which of the following is equal to ?
If and are defined as inverse functions, then . Thus, according to the definition of inverse functions, and given in the problem must be inverse functions.
If we want to find the inverse of a function, the most straighforward method is usually replacing with , swapping and , and then solving for .
We want to find the inverse of . First, we will replace with .
Next, we will swap and .
Lastly, we will solve for . The equation that we obtain in terms of will be in the inverse of , which equals .
We can treat as a proportion, . This allows us to cross multiply and set the results equal to one another.
We want to get y by itself, so let's divide both sides by x.
Next, we will add 3 to both sides.
To combine the right side, we will need to rewrite 3 so that it has a denominator of .
The answer is .
Example Question #67 : Algebraic Functions
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Example Question #64 : How To Find F(X)
Let the function f be defined by f(x)=x-t. If f(12)=4, what is the value of f(0.5*t)?
First we substitute in 12 for x and set the equation up as 12-t=4. We then get t=8, and substitute that for t and get f(0.5*8), giving us f(4). Plugging 4 in for x, and using t=8 that we found before, gives us:
f(4) = 4 - 8 = -4
Example Question #15 : Algebraic Functions
What is the value of the function f(x) = 6x2 + 16x – 6 when x = –3?
–108
96
–12
0
0
There are two ways to do this problem. The first way just involves plugging in –3 for x and solving 6〖(–3)〗2 + 16(–3) – 6, which equals 54 – 48 – 6 = 0. The second way involves factoring the polynomial to (6x – 2)(x + 3) and then plugging in –3 for x. The second way quickly shows that the answer is 0 due to multiplying by (–3 + 3).