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Lesson Example Discussion Quiz: Class Homework

Lesson

Title: Trigonometry function( sine, cosine, tangent)

Grade: 10-a Lesson: S3-L1

Explanation: Hello students, let us learn a new topic in SAT-2 today with definitions, concepts, examples, and worksheets included.

Lesson:

Definition: Sine (sin θ)

The ratio of the opposite side (to the angle) over the hypotenuse (longest side).

$1$

Explanation: The sine of an angle in a right-angled triangle is the ratio of the length of the side opposite the angle to the length of the hypotenuse.

In a unit circle, the sine of an angle is the y-coordinate of the point on the unit circle corresponding to that angle.

Definition: Cosine (cos θ)

The ratio of the adjacent side (closest to the angle) over the hypotenuse.

$2$

Explanation: The cosine of an angle in a right-angled triangle is the ratio of the length of the adjacent side to the length of the hypotenuse.

In a unit circle, the cosine of an angle is the x-coordinate of the point on the unit circle corresponding to that angle.

Definition: Tangent (tan θ)

The ratio of the opposite side over the adjacent side.

$3$

Explanation: The tangent of an angle in a right-angled triangle is the ratio of the length of the side opposite the angle to the length of the adjacent side.

In a unit circle, the tangent of an angle is the ratio of the sine to the cosine of that angle, i.e., \$"tan" "θ" = ("sin" "θ") / ("cos" "θ")\$.