Calculator ratio values
Use the angle unit and function named in the question. Round the final result to the requested precision
- Use degree mode Check the angle setting before entering a degree measurement
- Use the named key Enter the angle with sine, cosine or tangent as requested. The result is a ratio, so it has no degree symbol
- Round at the end Keep the calculator value until the requested final answer \(\displaystyle \begin{aligned}\sin 52^{\circ}&=0.7880107536\ldots\\\sin 52^{\circ}&\approx0.7880\end{aligned}\)
Worked example
Evaluate the ratio to four decimal places in degree mode
- \(\displaystyle \sin 52^{\circ}=0.7880107536\ldots\)Use the sine key after checking degree mode
- \(\displaystyle \sin 52^{\circ}\approx0.7880\)The next digit is one, so keep the fourth decimal digit. Include the final zero
Common mistakes
Difficulty levels
Questions about this topic
Why is there no degree symbol in the answer?+
The input is an angle. The output is a ratio of lengths, so it has no unit
Can a tangent value exceed one?+
Yes. The opposite side can be longer than the adjacent side
Should I round a ratio before using it to find a side?+
Keep the full calculator value when it is part of a longer calculation. Round only the requested final answer
Can I use a calculator?+
A calculator is allowed unless a question is marked no calculator
Which year level and chapter is this?+
Year 9 Mathematics, chapter 3: Pythagoras and trigonometry