All SAT II Math I Resources
Example Questions
Example Question #2 : Parabolas And Circles
What is the center of the circle with the following equation?
Remember that the basic form of the equation of a circle is:
This means that the center point is defined by the two values subtracted in the squared terms. We could rewrite our equation as:
Therefore, the center is
Example Question #2 : Parabolas And Circles
What is the area of the sector of the circle formed between the -axis and the point on the circle found at when the equation of the circle is as follows?
Round your answer to the nearest hundreth.
For this question, we will need to do three things:
- Determine the point in question.
- Use trigonometry to find the area of the angle in question.
- Use the equation for finding a sector area to finalize our answer.
Let us first solve for the coordinate by substituting into our equation:
Our point is, therefore:
Now, we need to calculate the angle formed between the origin and the point that we were given. We can do this using the inverse tangent function. The ratio of to is here:
Therefore, the angle is:
To solve for the sector area, we merely need to use our standard geometry equation. Note that the radius of the circle, based on the equation, is .
This rounds to .
Example Question #3 : Parabolas And Circles
What is the area of the sector of the circle formed between the -axis and the point on the circle found at when the equation of the circle is as follows?
Round your answer to the nearest hundreth.
For this question, we will need to do three things:
- Determine the point in question.
- Use trigonometry to find the area of the angle in question.
- Use the equation for finding a sector area to finalize our answer.
Let us first solve for the coordinate by substituting into our equation:
Our point is, therefore:
Now, we need to calculate the angle formed between the origin and the point that we were given. We can do this using the inverse tangent function. The ratio of to is here:
Therefore, the angle is:
To solve for the sector area, we merely need to use our standard geometry equation. Note that , based on the equation, is .
This rounds to .
Example Question #5 : Parabolas And Circles
If the center of a circle is at and it has a radius of , what positive point on the does it intersect?
Since you are looking for a point on the , your value will be zero.
The center of the circle is at the origin and radius is the distance from the center, so that means the point you are looking for must be points away from .
This can be two points on the but since you are looking for a positive one, your answer must be .
Example Question #1 : Symmetry
Given a point , what is the new value if this point is flipped across the line ?
The displacement between negative three and positive one is four.
This mean that after flipping the point, it must be symmetrical to its original location. The new point must also be 4 units to the right of the line.
The new point would be located at:
The answer is:
Example Question #1 : Symmetry
Which of the following symmetries applies to the graph of the relation
?
I) Symmetry with respect to the origin
II) Symmetry with respect to the -axis
III) Symmetry with respect to the -axis
I only
None of these
II only
III only
I, II and III
III only
The relation
is a circle with center and radius .
In other words, it is a circle with center at the origin, translated right units and up units (the radius is irrelevant to the question).
or
is this circle translated right zero units and up 2 units. The upshot is that the circle moves along the -axis only, and therefore is symmetric with respect to the -axis, but not the -axis. Also, as a consequence, it is not symmetric with respect to the origin.
Example Question #1 : Transformations
Reflect the point across the line and then across the origin.
Reflecting the point across the vertical line will only change the x-value, but not the y-value.
The point after this reflection is:
Rotating this point across the origin will swap the x and y-values.
The new point is:
Example Question #1 : Transformations
Let . If is equal to when flipped across the x-axis, what is the equation for ?
When a function is flipped across the x-axis, the new function is equal to . Therefore, our function is equal to:
Our final answer is therefore
Example Question #1 : Transformation
Let . If we let equal when it is flipped across the y-axis, what is the equation for ?
When a function is flipped across the y-axis, the resulting function is equal to . Therefore, to find our , we must substitute in for every is our equation:
Our final answer is therefore
Example Question #2 : Transformation
Let . If represents is shifted places to the right and places upwards, what is the equation for ?
When a function is transformed units upwards, the new function is equal to . Likewise, if is transformed units to the right, the new function is equal to . Therfore, we can first find the upwards transformation by adding to the function:
Now we can apply the horizontal transformation by replacing all 's in the function with . Our transformed function therefore becomes:
We then multiply this out to obtain:
Our final answer is therefore
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