All High School Math Resources
Example Questions
Example Question #43 : Understanding Radians And Conversions
How many radians are in ?
To convert degrees to radians, set up a ratio. The ratio of degrees to radians is .
Cross multiply.
Example Question #54 : The Unit Circle And Radians
How many radians are in ?
To solve this, use a proportion. The ratio of degrees to radians is .
Cross multiply:
Example Question #81 : Trigonometry
In the unit circle, what is the angle in radians that corresponds to the point (0, -1)?
On the unit circle, (0,-1) is the point that falls between the third and fourth quadrant. This corresponds to .
Example Question #82 : Trigonometry
What is the reference angle for ?
To find the reference angle, subtract (1 trip around the unit circle) from the given angle until you reach an angle which is less than .
Example Question #1 : Triangles
In this figure, side , , and . What is the value of angle ?
Undefined
Since , we know we are working with a right triangle.
That means that .
In this problem, that would be:
Plug in our given values:
Example Question #2 : Triangles
Let ABC be a right triangle with sides = 3 inches, = 4 inches, and = 5 inches. In degrees, what is the where is the angle opposite of side ?
We are looking for . Remember the definition of in a right triangle is the length of the opposite side divided by the length of the hypotenuse.
So therefore, without figuring out we can find
Example Question #1 : Trigonometric Functions And Graphs
In this figure, if angle , side , and side , what is the measure of angle ?
Undefined
Since , we know we are working with a right triangle.
That means that .
In this problem, that would be:
Plug in our given values:
Example Question #3 : Triangles
In this figure, , , and . What is the value of angle ?
Undefined
Notice that these sides fit the pattern of a 30:60:90 right triangle: .
In this case, .
Since angle is opposite , it must be .
Example Question #4 : Triangles
A triangle has angles of . If the side opposite the angle is , what is the length of the side opposite ?
The pattern for is that the sides will be .
If the side opposite is , then the side opposite will be .
Example Question #1 : Triangles
In , , , and . To the nearest tenth, what is ?
A triangle with these sidelengths cannot exist.
By the Triangle Inequality, this triangle can exist, since .
By the Law of Cosines:
Substitute the sidelengths and solve for :