few_shots: 
Example:
Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: fl_problem_001894_pos_0

HS_0
standard_description: Explain why a fraction a/b is equivalent to a fraction (n × a)/(n × b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves are the same size. Use this principle to recognize and generate equivalent fractions.
Grade 4 expectations in this domain are limited to fractions with denominators 2, 3, 4, 5, 6, 8, 10, 12, and 100.
problem_activity: Problem 1
What is the measure, in wedges, of the following angle?
[IMG]
A ray that turns all the way around its endpoint and back to its starting place has made a full turn. We say that the ray has turned 360
degrees
.
[IMG]
How many degrees has the ray turned from where it started?
[IMG]
[IMG]
[IMG]
Problem 2
Determine how many degrees the wedge created in Lesson 5 measures, and use that to create a makeshift protractor to measure benchmark angles.
Use a similar process to create a makeshift protractor that measures in increments of 45°.
Problem 3
Using the makeshift protractors you made in Anchor Task #2, find the measure, in degrees, of each of the following angles. If an angle can’t be measured precisely with either protractor, make an estimate.
| 1.            |https://d21royfkw9g4l6.cloudfront.net/HGpdLmPiXL2wEUGq7M9oOB_HN2R71.png|  |https://d21royfkw9g4l6.cloudfront.net/HGpdLmPiXL2wEUGq7M9oOB_HN2R71.png| image:: https://d21royfkw9g4l6.cloudfront.net/HGpdLmPiXL2wEUGq7M9oOB_HN2R71.png |     1.            |https://d21royfkw9g4l6.cloudfront.net/FMs2nYL35BSek6I79QzcBc_7N2YKT.png|  |https://d21royfkw9g4l6.cloudfront.net/FMs2nYL35BSek6I79QzcBc_7N2YKT.png| image:: https://d21royfkw9g4l6.cloudfront.net/FMs2nYL35BSek6I79QzcBc_7N2YKT.png      |
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| 1.            |https://d21royfkw9g4l6.cloudfront.net/6c8XNXS8LTq61hZkJBlXSF_CSHLNR.png|  |https://d21royfkw9g4l6.cloudfront.net/6c8XNXS8LTq61hZkJBlXSF_CSHLNR.png| image:: https://d21royfkw9g4l6.cloudfront.net/6c8XNXS8LTq61hZkJBlXSF_CSHLNR.png | 1.                     |https://d21royfkw9g4l6.cloudfront.net/uPouVZDNncCcCiLGZlYrBR_VUQXH3.png|  |https://d21royfkw9g4l6.cloudfront.net/uPouVZDNncCcCiLGZlYrBR_VUQXH3.png| image:: https://d21royfkw9g4l6.cloudfront.net/uPouVZDNncCcCiLGZlYrBR_VUQXH3.png |


aligns: no