CK-12 Foundation
Half Angle Formulas: Half-Angle Formulas
Slide the resource into your lesson plans. Young mathematicians use a slider to move a movie screen to the right position for optimal viewing. Along the way, they learn to apply the half angle formulas.
CK-12 Foundation
Finding Exact Trigonometric Values Using Double Angle Identities: Trig Values Using Double and Half Angle Formulas
The more you know, the more you can learn. Scholars apply the double angle and half angle formulas to determine trig values based on known values. They use an interactive that provides sine and cosine values to aid calculations.
Curated OER
Double-Angle and Half-Angle Formulas
In this college level Pre-Calculus worksheet, students use the double-angle and half-angle formulas to evaluate trigonometric expressions and solve trigonometric equations. The six page worksheet contains fifty-six problems. Answers are...
Curated OER
Half Angle Formula
For this half angle formula worksheet, students use half angle formulas to find the value of given angles. This one-page worksheet contains 1 multi-step problems.
Curated OER
Half Angle
Students calculate the solution using half angles formulas. In this calculus lesson plan, students identify the different properties of a triangle using trigonometric properties. They identify the mean, altitude and angles of a triangle.
EngageNY
Addition and Subtraction Formulas 2
Knowing the addition formulas allows for the calculations of double and half formulas. The fourth installment of 16 has the class use the addition formula to develop the double angle trigonometric formulas. Using the double formula,...
EngageNY
Mid-Module Assessment Task: Pre-Calculus Module 4
Challenge scholars to show what they know about properties and addition and subtraction formulas for trigonometric functions. The resource provides a mid-unit check on the progress toward mastery of trigonometric concepts. The areas...
Scholastic
Study Jams! Area of a Triangle
Even though there is a wide variety of different triangles in the world, knowing a single equation allows us to find the area of each and every one of them. Follow along with this step-by-step presentation as Zoe clearly models how to...
Shodor Education Foundation
Triangle Area
While the lesson focuses on right triangles, this activity offers a great way to practice the area of all triangles through an interactive webpage. The activity begins with the class taking a square paper and cutting in in half; can they...
Curated OER
Angle Sum and Difference
In this angle sum and difference worksheet, 11th graders solve 10 different problems related to determining the angle sum and difference of numbers. First, they determine the exact value of sine and cosine degrees. Then, students utilize...
Radford University
Pizza Sector Task
Gobble up a slice of the task. Scholars first consider the area of a whole pizza, half a pizza, and a quarter of a pizza. They then consider other central angles and develop a formula for the area of any sector of a circle.
Illustrative Mathematics
Seven Circles III
A basic set-up leads to a surprisingly complex analysis in this variation on the question of surrounding a central circle with a ring of touching circles. Useful for putting trigonometric functions in a physical context, as well as...
Virginia Department of Education
Arc Length and Area of a Sector
What do skateboarding and baked goods have in common with math? You can use them to connect half-pipe ramps and cakes to arcs and sectors. Pupils compare the lengths of three different ramp options of a skate park. They calculate the...
101 Questions
Lucky Cow
Cutting the cheese isn't a joke. Scholars observe a wedge of cheese and must determine how to cut it in half horizontally. They apply their knowledge of sectors to determine the most accurate way to slice the cheese.
EngageNY
Using Trigonometry to Determine Area
What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...
Illustrative Mathematics
Same Base and Height, Variation 1
Four triangles are depicted for learners to construct on a geoboard. They compute and compare the areas, and so meet one of the sixth grade Common Core standards for geometry. Note that the set of triangles does not include a right...
Curated OER
Travel Triangles
Students demonstrate and understanding of the three types of angles using triangles and quadrilaterals. In this angles lesson plan, students learn about acute, obtuse and right angles. They use cut-outs to find the areas of triangles and...
Curated OER
Solve Word Problems with Geometry
For this geometry worksheet, students solve word problems having to do with lines, angles, shapes, area, perimeter, and more. Students complete 57 problems total.
EngageNY
Similar Triangles in Circle-Secant (or Circle-Secant-Tangent) Diagrams
First angle measures, now segment lengths. High schoolers first measure segments formed by secants that intersect interior to a circle, secants that intersect exterior to a circle, and a secant and a tangent that intersect exterior to a...
Curated OER
Math Handbook: Trigonometry
You'll be spinning in unit circles once you read through this jumbo-sized resource of everything you need to know about trigonometry. Each page has color-coded examples with explicit directions that detail the problems and formulas.
Alabama Learning Exchange
It's Around There Somewhere! Perimeter, and Circumference
Explore the concept of building equations for perimeter and circumference. Learners use rulers to measure the perimeter of half a sheet of paper. Then fold the sheet of paper numerous times, each time measuring perimeter. Learners use...
Curated OER
Worksheet 21
In this math worksheet, students practice using the appropriate formula developed to solve the word problems. They find the correct operation to find the answer to each.
Curated OER
Finding the Area of Triangles
Twelfth graders apply the formula for finding the area of a triangle to various problems. They work real life problems for finding the area of a bathroom and the cost of tiling it. They play a game, Triangle Bingo, where they match...
Dick Blick Art Materials
Start with a Circle...
The Golden Ratio. The Divine Proportion. Yup. It's math and art blended into one colorful activity. Young artists combine colored tissue paper circles and parts of circles to create geometric patterns. As a bonus, kids get to figure out...