1.
Which is a main function used in trigonometry?
Correct Answer
A. Sine
Explanation
The main function used in trigonometry is the sine function. Sine is a mathematical function that relates the angles of a right triangle to the lengths of its sides. It is commonly used to find the unknown side lengths or angles of a triangle. The sine function is defined as the ratio of the length of the side opposite the angle to the length of the hypotenuse. It is represented by the abbreviation "sin" in trigonometric calculations.
2.
The ratio of the length of the side that is opposite an angle to the length of the longest side of the triangle (the hypotenuse) is...
Correct Answer
A. The sine of the angle
Explanation
The sine of an angle in a right triangle is defined as the ratio of the length of the side opposite the angle to the length of the hypotenuse. Therefore, the correct answer is "The sine of the angle" because it directly corresponds to the given ratio in the question.
3.
What is used to understand sines and cosines of angles found in right triangles?
Correct Answer
B. Unit circle
Explanation
The unit circle is used to understand sines and cosines of angles found in right triangles. The unit circle is a circle with a radius of 1, centered at the origin of a coordinate plane. By placing the angle in standard position on the unit circle, the x-coordinate gives the cosine value and the y-coordinate gives the sine value of the angle. This allows us to easily find the sine and cosine of any angle in a right triangle.
4.
At what point is the origin of the unit circle located?
Correct Answer
D. Centre
Explanation
The origin of the unit circle is located at the center. The center is the point from which all points on the circle are equidistant. In the case of the unit circle, which has a radius of 1, the center is at the point (0,0) on the coordinate plane.
5.
A circle with a radius of one is referred to as...
Correct Answer
C. Unit circle
Explanation
A circle with a radius of one is referred to as a unit circle because it has a radius of one unit. The term "unit" in mathematics is often used to refer to a standard or fixed quantity, and in this case, the unit circle serves as a standard reference for measuring angles and trigonometric functions. It is commonly used in calculus, geometry, and trigonometry to simplify calculations and visualize relationships between angles and coordinates on the Cartesian plane.
6.
What is the circumference of the unit circle?
Correct Answer
A. 2pi
Explanation
The circumference of a circle is the distance around its edge. The unit circle has a radius of 1, which means its diameter is 2. The formula for the circumference of a circle is C = 2πr, where r is the radius. In this case, the radius is 1, so the circumference of the unit circle is 2π.
7.
The radian measure of the arc on a circle corresponding to a given value of tangent is referred to as...
Correct Answer
A. Arctan
Explanation
The radian measure of the arc on a circle corresponding to a given value of tangent is referred to as "Arctan". Arctan is the inverse function of the tangent function and is used to find the angle whose tangent is a given value. It is commonly used in trigonometry to solve for angles in right triangles.
8.
What is the reciprocal of the tangent function?
Correct Answer
B. Cotangent
Explanation
The reciprocal of the tangent function is the cotangent function. The cotangent of an angle is equal to the ratio of the adjacent side to the opposite side in a right triangle. It is the inverse of the tangent function, meaning that if the tangent of an angle is x, then the cotangent of the same angle is 1/x. Therefore, the correct answer is cotangent.
9.
What is the inverse of the tangent function?
Correct Answer
D. Arctangent
Explanation
The inverse of the tangent function is the arctangent function. This means that if we have the value of the tangent of an angle, we can use the arctangent function to find the measure of that angle. The arctangent function is the opposite operation of the tangent function, just like subtraction is the opposite of addition. Therefore, the correct answer is arctangent.
10.
What is the complementary trigonometric function of the sine?
Correct Answer
C. Cosine
Explanation
The complementary trigonometric function of the sine is the cosine. In trigonometry, the sine of an angle in a right triangle is defined as the ratio of the length of the side opposite the angle to the length of the hypotenuse. The cosine, on the other hand, is defined as the ratio of the length of the adjacent side to the length of the hypotenuse. Since the sine and cosine are complementary functions, they are always equal to each other when added together. Therefore, the correct answer is cosine.