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Example Questions
Example Question #1 : Determine The Symmetry Of An Equation
Is the following function symmetrical about the y axis (is it an even function)?
Insufficient Information
Not a function
Yes
No
No
For a function to be even, it must satisfy the equality
Likewise if a function is even, it is symmetrical about the y-axis
Therefore, the function is not even, and so the answer is No
Example Question #1 : Determine The Symmetry Of An Equation
Algebraically check for symmetry with respect to the x-axis, y axis, and the origin.
Symmetrical about the x-axis
Symmetrical about the origin
Symmetrical about the y-axis
No symmetry
Symmetrical about the x-axis
For a function to be symmetrical about the y-axis, it must satisfy so there is not symmetry about the y-axis
For a function to be symmetrical about the x-axis, it must satisfy so there is symmetry about the x-axis
For a function to be symmetrical about the origin, you must replace y with (-y) and x with (-x) and the resulting function must be equal to the original function.
-So there is no symmetry about the origin, and the answer is Symmetrical about the x-axis
Example Question #1 : Determine The Symmetry Of An Equation
Algebraically check for symmetry with respect to the x-axis, y axis, and the origin.
Symmetry about the x-axis, and y-axis
Symmetry about the x-axis
Symmetry about the y-axis
Symmetry about the y-axis and origin
Symmetry about the x-axis, y-axis, and origin
Symmetry about the y-axis
For a function to be symmetrical about the y-axis, it must satisfy so there is symmetry about the y-axis
For a function to be symmetrical about the x-axis, it must satisfy
so there is not symmetry about the x-axis
For a function to be symmetrical about the origin, you must replace y with (-y) and x with (-x) and the resulting function must be equal to the original function.
So there is no symmetry about the origin.
Example Question #1 : Determine The Symmetry Of An Equation
Algebraically check for symmetry with respect to the x-axis, y-axis, and the origin.
Symmetry about the x-axis and y-axis
Symmetry about the x-axis, y-axis, and origin
Symmetry about the y-axis
Symmetry about the x-axis
Symmetry about the y-axis and the origin
Symmetry about the y-axis
For a function to be symmetrical about the y-axis, it must satisfy
so there is symmetry about the y-axis
For a function to be symmetrical about the x-axis, it must satisfy
so there is not symmetry about the x-axis
For a function to be symmetrical about the origin, you must replace y with (-y) and x with (-x) and the resulting function must be equal to the original function.
So there is no symmetry about the origin, and the credited answer is "symmetry about the y-axis".
Example Question #1 : Determine The Symmetry Of An Equation
Which of the following best describes the symmetry of with respect to the x-axis, y-axis, and the origin.
No symmetry
Symmetrical about the y-axis
Symmetrical about the x-axis
Symmetrical about the origin
Symmetrical about the x-axis
For a function to be symmetrical about the y-axis, it must satisfy
so there is not symmetry about the y-axis
For a function to be symmetrical about the x-axis, it must satisfy
so there is symmetry about the x-axis
For a function to be symmetrical about the origin, you must replace y with (-y) and x with (-x), and the resulting function must be equal to the original function.
So there is no symmetry about the origin, and the answer is Symmetrical about the x-axis.
Example Question #1 : Determine The Symmetry Of An Equation
Yes
No
The given information does not include a function
There is insufficient information to determine the answer
Example Question #1 : Write A Quadratic Equation When Given Its Solutions
Which of the following could be the equation for a function whose roots are at and ?
If the roots of the equation are at x= -4 and x=3, then we can work backwards to see what equation those roots were derived from. If we factored a quadratic equation and obtained the given solutions, it would mean the factored form looked something like:
Because this is the form that would yield the solutions x= -4 and x=3. If we work backwards and multiply the factors back together, we get the following quadratic equation:
Example Question #1 : Write A Quadratic Equation When Given Its Solutions
Given roots . Write a quadratic polynomial that has as roots.
We can make a quadratic polynomial with by mutiplying the linear polynomials they are roots of, and multiplying them out.
Start
Distribute the negative sign
FOIL the two polynomials. This means multiply the firsts, then the outers, followed by the inners and lastly, the last terms.
Simplify
Example Question #1 : Write A Quadratic Equation When Given Its Solutions
If we know the solutions of a quadratic equation, we can then build that quadratic equation.
Find the quadratic equation when we know that:
and are solutions.
Since we know the solutions of the equation, we know that:
We simply carry out the multiplication on the left side of the equation to get the quadratic equation.
Example Question #1 : Write A Quadratic Equation When Given Its Solutions
Which of the following is a quadratic function passing through the points and ?
These two points tell us that the quadratic function has zeros at , and at .
These correspond to the linear expressions , and .
Expand their product and you arrive at the correct answer.
If the quadratic is opening up the coefficient infront of the squared term will be positive. Thus we get:
.
If the quadratic is opening down it would pass through the same two points but have the equation:
.
Since only is seen in the answer choices, it is the correct answer.
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