Use inverse functions to find an angle

In this lesson, we will find a missing angle in a given triangle using the inverse trigonometric functions. We will need to interpret which trigonometric ratio to use, and rearrange it.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Use your calculator find the value of cos(56) to 3 decimal places.

1/3

Q2.Use your calculator find the value of tan(89) to 3 decimal places.

2/3

Q3.Use your calculator to work out the size of sinѲ = 0.21 . Give your answer to one decimal place.

3/3

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.Use your calculator find the value of cos(56) to 3 decimal places.

1/3

Q2.Use your calculator find the value of tan(89) to 3 decimal places.

2/3

Q3.Use your calculator to work out the size of sinѲ = 0.21 . Give your answer to one decimal place.

3/3

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Use inverse functions to find an angle

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Which of the trigonometry ratios will be required to find the missing angle in this question?

1/3

Q2.Find the missing angle, giving your answer to 1 decimal place.

2/3

Q3.Find the missing angle, giving your answer to 1 decimal place.

3/3

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Use inverse functions to find an angle

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Which of the trigonometry ratios will be required to find the missing angle in this question?

1/3

Q2.Find the missing angle, giving your answer to 1 decimal place.

2/3

Q3.Find the missing angle, giving your answer to 1 decimal place.

3/3

Lesson summary: Use inverse functions to find an angle

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