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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 #1031 : Algebra
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 #101 : Algebraic Functions
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
6
12
8
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 #63 : How To Find F(X)
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 #64 : 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 #68 : Algebraic Functions
.
Example Question #105 : Algebraic Functions
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 #16 : Algebraic Functions
What is the value of the function f(x) = 6x2 + 16x – 6 when x = –3?
96
0
–12
–108
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).
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